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Dell Latitude 7400 2-in-1 (i7-8665U) Convertible Review

Hot contender. Dell’s premium business models have never been more XPS-like, but with the sweeping changes come significant challenges. With its Core i7-8665U CPU, 16 GB RAM, and NVMe SSD, the $2,800 Latitude 7400 2-in-1 certainly isn’t slow, but can it take the heat? Let’s find out. Update: i5 version is a better match for the cooling solution

A common thread has permeated our reviews of the last few generations of high-end business laptops: they’re becoming increasingly consumer-like. The goal of manufacturers in pursuing this evolution has been to incorporate some of the exciting, stylish design language of XPS/Spectre/Yoga devices without compromising the basic tenets of what constitutes a solid office companion. It’s a difficult balancing act because, while thinness/attractiveness and practicality/versatility aren’t exactly mutually exclusive, it certainly makes the engineer’s job a lot harder.

Few manufacturers have been more transparent in their journey toward luxury business-grade utopianism than Dell, but until now, their Latitude 7390 2-in-1 has probably been the closest thing to a larger high-end business convertible that the company has produced. Several months ago, we even saw the Latitude 7000 series machines add an optional sleek aluminum casing, inching them ever closer to their XPS cousins.

Today, the Latitude 7400 2-in-1 is the next massive step toward this careful merger of design philosophies. Adorned also in aluminum (versus the matte black-painted magnesium of yore), the 7400 includes a 14” display—the largest to date in the Dell Latitude family. Our review unit also packs a Whiskey Lake Intel Core i7-8665U CPU, 16 GB LPDDR3 RAM, and a 512 GB NVMe SSD. There are no dedicated graphics options, but with specs like those, this machine should have little problem dealing with the rigors of the daily office grind. Dell also promises long battery runtimes and introduces their ambitious ExpressSign-in functionality, which leverages proximity sensors and facial recognition to seamless lock/unlock your machine as you leave or approach it. At a pricey $2,800, we should expect little short of perfection.

But the sweeping changes absolutely bring challenges along with them. In our full review today, as always, we’ll lay bare the results of our relentless array of scientific measurements and benchmarks in pursuit of a full picture of just what does and doesn’t work on the Latitude 7400 2-in-1. Let’s go. 

(June 7, 2019 update: We've rerun some performance tests including CineBench R15, PCMark 10, and Prime95 on a different review unit with more stable results. Our comments and numbers have been revised to reflect the new findings.)

(September 2, 2019 update: Since the Core i7 model quickly overpowers the cooling solution, we have now taken a look at the Core i5 SKU as well. We performed another round of PCMark 10 and CineBench R15 loop tests and added the results to the performance paragraphs.)

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Dell Latitude 7400 2-in-1 (Latitude 7400 Series)
Graphics adapter
Intel UHD Graphics 620, Core: 300 - 1150 MHz, 25.20.100.6577
Memory
16384 MB 
, LPDDR3
Display
14 inch 16:9, 1920 x 1080 pixel 157 PPI, 10-point multitouch, native pen support, SHP14A2, IPS, glossy: yes
Mainboard
Intel Cannon Point-LP
Storage
Toshiba XG6 KXG60ZNV512G, 512 GB 
Soundcard
Realtek ALC295 @ Intel Sunrise Point-LP PCH - High Definition Audio Controller
Connections
2 USB 3.0 / 3.1 Gen1, 2 USB 3.1 Gen2, 2 Thunderbolt, 1 HDMI, 1 Kensington Lock, Audio Connections: 3.5 mm combo audio, Card Reader: microSD, Brightness Sensor, Sensors: proximity sensor for Dell ExpressSign-in, gyroscope, accelerometer,
Networking
Intel Wireless-AC 9560 (a/b/g/n = Wi-Fi 4/ac = Wi-Fi 5), Bluetooth 5.0
Size
height x width x depth (in mm): 15 x 320 x 202 ( = 0.59 x 12.6 x 7.95 in)
Battery
78 Wh Lithium-Polymer, ExpressCharge capable
Operating System
Microsoft Windows 10 Pro 64 Bit
Camera
Webcam: 720p
Primary Camera: 1 MPix
Additional features
Speakers: 2.0 bottom-mounted, Keyboard: Chiclet, Keyboard Light: yes, 12 Months Warranty
Weight
1.512 kg ( = 53.33 oz / 3.33 pounds), Power Supply: 356 g ( = 12.56 oz / 0.78 pounds)
Note: The manufacturer may use components from different suppliers including display panels, drives or memory sticks with similar specifications.

 

Case

The Latitude 7400 2-in-1 is nothing if not attractive. Stunning, even. It’s the closest Dell’s ever gotten to a business-grade MacBook Pro competitor, right down to the heavy brushed aluminum casing. While predominantly matte in its finish, the shiny dual hinge covers and polished edges stand out as flashier than we’re used to in the professional segment. Still, in spite of its relative pomp, it’s undoubtedly suited for use in a boardroom.

As we’ve come to expect from the Latitude 7000 series machines, very little flex is detectable at any point on the case, and the machine rests firmly on a surface thanks to its large horizontal rubber feet; it's roughly comparable to the rigidity of an XPS 15, which is overall very good. The display lid is solid, effectively dispelling any twisting efforts and stably supported by the two hinges, which succumb only very slightly to vibrations under heavy typing and in transit. It’s almost possible to open the machine single-handedly, but the final ascent does require pressure on the base to prevent it from lifting off the surface.

At 1.512 kg (equipped with the larger 6-cell internal battery), the system is similar in weight to its predecessor, the Latitude 7490, which registered 1.561 kg by comparison. The footprint has shrunk significantly, however: at just 320 mm x 202 mm, it’s nearly 12% smaller than before. It’s also quite a bit thinner (15 mm, down from 17.9 mm).

333 mm / 13.1 inch 229 mm / 9.02 inch 17.05 mm / 0.671 inch 1.4 kg3.14 lbs324 mm / 12.8 inch 224 mm / 8.82 inch 20 mm / 0.787 inch 1.6 kg3.61 lbs327 mm / 12.9 inch 226 mm / 8.9 inch 13.9 mm / 0.547 inch 1.4 kg3.09 lbs321.4 mm / 12.7 inch 215 mm / 8.46 inch 16.9 mm / 0.665 inch 1.4 kg2.98 lbs323 mm / 12.7 inch 217 mm / 8.54 inch 15 mm / 0.591 inch 1.1 kg2.49 lbs320 mm / 12.6 inch 202 mm / 7.95 inch 15 mm / 0.591 inch 1.5 kg3.33 lbs

Connectivity

While the case has shrunk, only a few notable changes in terms of port selection apply. For starters, the Ethernet port is now completely missing—because the case is simply too thin for it to be practical, even with the hinge-based design of the last few revisions. In addition to that, one of the two USB 3.0 ports on the left side of the machine has now been exchanged for (upgraded to?) a ThunderBolt 3 port—but this port also replaces the dedicated charging port. Some people might consider this “forward-thinking” move toward a ThunderBolt-driven future a positive one, but others will lament the reduction in number of conventional USB Type-A ports and the dual obligations of the fourth port. It is true at least that now both Type-C ports carry DisplayPort connectivity, hypothetically opening the door to three-monitor configurations without the need for a docking station. External displays that support Type-C charging will also be able to charge the Latitude 7400 2-in-1 simultaneously.

Port organization, meanwhile, is practically identical to the 7490/7480. The ports are somewhat closely-spaced, but they’re all side-mounted and logically positioned. We have few complaints here apart from the usual concerns about larger connectors crowding out adjacent ports.

Left: Thunderbolt 3 x 2 + charging ports, HDMI USB 3.1 powered
Left: Thunderbolt 3 x 2 + charging ports, HDMI USB 3.1 powered
Right: 3.5 mm combo audio, microSD, SIM card tray, USB 3.1 powered, Kensington Lock
Right: 3.5 mm combo audio, microSD, SIM card tray, USB 3.1 powered, Kensington Lock

SD Card Reader

The integrated microSD card reader performs very well and comes close to topping our comparison charts, with 172.1 MB/s in our JPG copy test and 209.62 MB/s in the AS SSD Sequential Read Test.

SDCardreader Transfer Speed
average JPG Copy Test (av. of 3 runs)
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
  (Toshiba Exceria Pro M501)
191.1 MB/s ∼100% +11%
Dell Latitude 7400 2-in-1
  (Toshiba Exceria Pro M501 UHS-II)
172.1 MB/s ∼90%
HP Pavilion x360 14-cd0002ng
  (Toshiba Exceria Pro SDXC 64 GB UHS-II)
68.2 MB/s ∼36% -60%
Average of class Convertible
  (7.5 - 197, n=127)
61.3 MB/s ∼32% -64%
Asus ZenBook Flip 14 UX461UA
  (Toshiba Exceria Pro M501 microSDXC 64GB)
33.2 MB/s ∼17% -81%
maximum AS SSD Seq Read Test (1GB)
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
  (Toshiba Exceria Pro M501)
223.9 MB/s ∼100% +7%
Dell Latitude 7400 2-in-1
  (Toshiba Exceria Pro M501 UHS-II)
209.62 MB/s ∼94%
HP Pavilion x360 14-cd0002ng
  (Toshiba Exceria Pro SDXC 64 GB UHS-II)
83.2 MB/s ∼37% -60%
Average of class Convertible
  (21.7 - 246, n=125)
75.8 MB/s ∼34% -64%
Asus ZenBook Flip 14 UX461UA
  (Toshiba Exceria Pro M501 microSDXC 64GB)
36.5 MB/s ∼16% -83%

Communication

Again, there’s no longer any Ethernet connection without an adapter—but at least the wireless connectivity is rock-solid. Powered by an Intel Wireless-AC 9560 adapter, the 7400 2-in-1 dominates most other competitors with WLAN receive/transmit speeds topping 600 Mb/s (we are currently limited in testing by a 1 Gbps server, so the 9560 actually theoretically can go higher).

The Intel adapter also includes Bluetooth 5.0.

Networking
iperf3 Client (receive) TCP 1 m 4M x10
Dell Latitude 7400 2-in-1
Intel Wireless-AC 9560
655 MBit/s ∼100%
HP Elitebook x360 1040 G5
Intel Dual Band Wireless-AC 8265
654 MBit/s ∼100% 0%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel Dual Band Wireless-AC 8265
633 MBit/s ∼97% -3%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel Dual Band Wireless-AC 8265
540 MBit/s ∼82% -18%
Asus ZenBook Flip 14 UX461UA
Intel Dual Band Wireless-AC 8265
491 MBit/s ∼75% -25%
Average of class Convertible
  (28.7 - 688, n=141)
490 MBit/s ∼75% -25%
HP Pavilion x360 14-cd0002ng
RealTek Semiconductor, Device ID: C821
271 (min: 261, max: 290) MBit/s ∼41% -59%
iperf3 Client (transmit) TCP 1 m 4M x10
Asus ZenBook Flip 14 UX461UA
Intel Dual Band Wireless-AC 8265
668 MBit/s ∼100% +10%
Dell Latitude 7400 2-in-1
Intel Wireless-AC 9560
607 MBit/s ∼91%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel Dual Band Wireless-AC 8265
511 MBit/s ∼76% -16%
Average of class Convertible
  (36.4 - 685, n=141)
498 MBit/s ∼75% -18%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel Dual Band Wireless-AC 8265
494 MBit/s ∼74% -19%
HP Elitebook x360 1040 G5
Intel Dual Band Wireless-AC 8265
477 MBit/s ∼71% -21%
HP Pavilion x360 14-cd0002ng
RealTek Semiconductor, Device ID: C821
325 (min: 314, max: 340) MBit/s ∼49% -46%

Security

As usual, various security hardware authentication bundles exist for the Latitude 7400 2-in-1. However, the real story here is Dell’s new ExpressSign-in functionality, which seeks to lock/unlock your machine automatically through the synergistic use of a proximity sensor and IR facial recognition. We will test this feature as part of a separate article.

Either of these features can be disabled via the ExpressSign-in tray icon in Windows painlessly, as well as configured to automatically disengage when docked or connected to an external display.

Accessories

The Latitude 7400 ships with a single 90 W USB-C power adapter weighing 356 g. Again, after the move away from the proprietary 19.5 W Dell charging port, all older AC adapters will no longer work with this model.

Dell also provided us with an Active Stylus Pen (sold separately, $42), which works seamlessly with the Latitude 7400 2-in-1 display. We’ve reviewed this pen on multiple occasions in the past but in short, while it works well enough, it’s not quite as natural a writing experience as that of the Microsoft Surface products. The tips don’t feel quite as authentic, and the side buttons lack the defined feedback of the Surface Pen buttons.

The 90 W USB Type-C power adapter
The 90 W USB Type-C power adapter
The Dell Active Stylus Pen
The Dell Active Stylus Pen

Maintenance

As is expected of a high-end business laptop, maintenance is relatively straightforward on the Latitude 7400 2-in-1. Ten Phillips-head screws secure the bottom cover to the machine, which can then be (carefully!) pried away from within either hinge cavity to reveal the internal FRUs. These include the battery, M.2 SSD, CMOS battery, heatsink/fan, speakers, and WLAN/WWAN adapters. The system memory is soldered directly to the board and is not replaceable or upgradeable.

The internal components/FRUs
The internal components/FRUs

Warranty

The Latitude 7400 2-in-1 spec sheet we received quotes a 1-year depot warranty, but our review unit (and all listed units on Dell’s website) include a 3-year on-site warranty, which is typical for Latitude 7000 series machines. It appears that a 3-year on-site warranty (as expected) is typical.

Input Devices

Keyboard

Overall, the Latitude 7400 2-in-1 keyboard is very good. Key travel seems only slightly shorter than that of its predecessors (it’s still relatively long travel), actuation force is ever-so-slightly higher than before, and—although keystrokes are quiet—feedback is fairly sharp. This makes for a nearly-immediately comfortable typing experience, and one that’s very similar to previous Latitude 7000 series machines as well as the ThinkPad AccuType keyboards.

The layout is also very similar to previous models, though some key functions have been shuffled around to make room for PrtSc, Home, End, Insert, and Delete keys along the top right of the keyboard—an improvement by our judgment, as Home and End were previously located as secondary functions on the Left/Right arrow keys. Speaking of which, the arrow keys are still half-height, but they’re comfortable enough to use. PageUp/PageDown keys flank the sides of the Up arrow key, which is a sensible arrangement.

The keys are evenly backlit and feature well-contrasted dark backgrounds against white labels for easy visibility. The backlight is adjustable in three steps (Off, Dim, and Bright).

Easy to see whether light...
Easy to see whether light...
...or dark.
...or dark.

Touchpad

The glass touchpad makes for effortless finger gliding.
The glass touchpad makes for effortless finger gliding.

The Latitude 7400 2-in-1 finally also adopts the glass touchpad of its XPS cousins. This is, by our judgment, a definite improvement over the matte plastic pads of before, whose finish invariably would wear off from years of heavy use and which were more resistant to finger gliding than the smooth glass varieties.

The pad measures 104 mm x 59 mm which seems large enough for the screen size and resolution. It features integrated buttons which—while never as reliable as their separate, physical counterparts—are high-quality and worked well throughout our testing period. Cursor movement, thanks to Microsoft Precision drivers, is nearly lag-free and very accurate.

Display

Subpixel array
Subpixel array

There is but a single display option for the Latitude 7400 2-in-1: a 14-inch, FHD (1920x1080), IPS touchscreen with a glossy Corning Gorilla Glass 5 finish. The display also features Active Pen support. Touch interface was accurate on our review unit and the Dell Active Pen worked well in conjunction with it also.

At a PPI of 157, FHD resolution seems perfectly practical for a machine of this size; for higher-end displays with more real estate and color accuracy, the XPS series exists. Business users are likely to appreciate the improved battery life of a lower-resolution panel as well, so there are benefits to this choice apart from simply cost.

Subjectively, color gamut, saturation, and contrast seem good on our test unit. Brightness seems perhaps a bit on the low side, but it’s fine for everyday indoor use. We also didn’t notice any untoward clouding or backlight bleed even in the dark on purely black screens. It’s a very pleasant display overall, though it absolutely is highly reflective (more on this later).

263.3
cd/m²
262.5
cd/m²
250.8
cd/m²
291
cd/m²
277.2
cd/m²
278
cd/m²
253.6
cd/m²
242.1
cd/m²
252.5
cd/m²
Distribution of brightness
SHP14A2
X-Rite i1Pro Basic 2
Maximum: 291 cd/m² Average: 263.4 cd/m² Minimum: 12.52 cd/m²
Brightness Distribution: 83 %
Center on Battery: 277.2 cd/m²
Contrast: 1386:1 (Black: 0.2 cd/m²)
ΔE Color 2.1 | 0.6-29.43 Ø6, calibrated: 1.03
ΔE Greyscale 3.4 | 0.64-98 Ø6.3
100% sRGB (Argyll 3D) 64% AdobeRGB 1998 (Argyll 3D)
Gamma: 2.241
Dell Latitude 7400 2-in-1
SHP14A2, IPS, 14, 1920x1080
HP Pavilion x360 14-cd0002ng
Chi Mei CMN14D9, IPS, 14, 1920x1080
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Lenovo 40AE / B140QAN02.0, IPS Dolby Vision HDR, 14, 2560x1440
Asus ZenBook Flip 14 UX461UA
BOE NV140FHM-N62, IPS, 14, 1920x1080
HP Elitebook x360 1040 G5
AU Optronics AUO533D, IPS, 14, 1920x1080
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Lenovo LEN40A9 / AUO B140HAK02.3, IPS, 14, 1920x1080
Response Times
29%
18%
-18%
-24%
32%
Response Time Grey 50% / Grey 80% *
56 (31.6, 24.4)
44 (24, 20)
21%
56.8 (21.2, 35.6)
-1%
44 (24, 20)
21%
70.8 (34.8, 36)
-26%
40 (18, 22)
29%
Response Time Black / White *
38 (22.8, 15.2)
30 (17, 13)
21%
24 (6.8, 17.2)
37%
33 (19, 14)
13%
34.4 (18.8, 15.6)
9%
25 (14, 11)
34%
PWM Frequency
1667 (24)
2439 (30)
46%
200 (90)
-88%
735.3 (100)
-56%
Screen
-51%
17%
-42%
-4%
3%
Brightness middle
277.2
225
-19%
562
103%
302
9%
416.3
50%
298
8%
Brightness
263
195
-26%
522
98%
288
10%
400
52%
287
9%
Brightness Distribution
83
72
-13%
86
4%
90
8%
89
7%
91
10%
Black Level *
0.2
0.14
30%
0.3
-50%
0.57
-185%
0.29
-45%
0.2
-0%
Contrast
1386
1607
16%
1873
35%
530
-62%
1436
4%
1490
8%
Colorchecker DeltaE2000 *
2.1
5.44
-159%
2.8
-33%
5.17
-146%
2.69
-28%
2.19
-4%
Colorchecker DeltaE2000 max. *
5.91
20.38
-245%
5.8
2%
7.68
-30%
4.95
16%
4.39
26%
Colorchecker DeltaE2000 calibrated *
1.03
2.13
-107%
1.67
-62%
Greyscale DeltaE2000 *
3.4
3.98
-17%
4.5
-32%
3.26
4%
2.9
15%
1.97
42%
Gamma
2.241 98%
2.32 95%
2.16 102%
2.45 90%
2.4 92%
2.43 91%
CCT
6030 108%
6163 105%
7205 90%
7142 91%
6623 98%
6571 99%
Color Space (Percent of AdobeRGB 1998)
64
39
-39%
88.9
39%
55
-14%
60.1
-6%
62
-3%
Color Space (Percent of sRGB)
100
62
-38%
100
0%
85
-15%
94.5
-5%
95
-5%
Total Average (Program / Settings)
-11% / -32%
18% / 17%
-30% / -37%
-14% / -9%
18% / 7%

* ... smaller is better

We measured an average brightness of 263.4 cd/m², which is below Dell’s quoted value of 300 cd/m². Distribution is only around 83% on our review unit, but it’s not a noticeable discrepancy in general use. We computed a contrast ratio of 1386:1 based on a black value reading of 0.2 cd/m², which is very good overall.

By our measurements, the display manages 100% coverage of the sRGB spectrum and 64% of AdobeRGB. This is quite good overall and only beaten by the Lenovo ThinkPad X1 Yoga in today’s comparison field. Although it isn’t shown, these results are roughly equivalent to what we measured from last year’s Latitude 7490 contender.

vs. sRGB
vs. sRGB
vs. AdobeRGB
vs. AdobeRGB
vs. HP EliteBook x360 1040 G5
vs. HP EliteBook x360 1040 G5
vs. Lenovo X1 Carbon G6
vs. Lenovo X1 Carbon G6
vs. ZenBook Flip 14
vs. ZenBook Flip 14
vs. ThinkPad X1 Yoga
vs. ThinkPad X1 Yoga

Color accuracy is also impressive. ColorChecker and Greyscale DeltaE averages of 2.1 and 3.4, respectively, suggest only a slight bit of inaccuracy out of the box, though most users won’t mind in the slightest as it’s virtually imperceptible to the naked eye. Still, calibration makes all the difference (post-calibration, these values drop further to 1.67 and 1.5). A measured CCT Average of 6030 (ideal: 6500) and Total Gamma of 2.241 (ideal: 2.2) are also not far off the mark.

Color analysis (pre-calibration)
Color analysis (pre-calibration)
Saturation sweeps (pre-calibration)
Saturation sweeps (pre-calibration)
Grayscale analysis (pre-calibration)
Grayscale analysis (pre-calibration)
Color analysis (post-calibration)
Color analysis (post-calibration)
Saturation sweeps (post-calibration)
Saturation sweeps (post-calibration)
Grayscale analysis (post-calibration)
Grayscale analysis (post-calibration)

Display Response Times

Display response times show how fast the screen is able to change from one color to the next. Slow response times can lead to afterimages and can cause moving objects to appear blurry (ghosting). Gamers of fast-paced 3D titles should pay special attention to fast response times.
       Response Time Black to White
38 ms ... rise ↗ and fall ↘ combined↗ 22.8 ms rise
↘ 15.2 ms fall
The screen shows slow response rates in our tests and will be unsatisfactory for gamers.
In comparison, all tested devices range from 0.8 (minimum) to 240 (maximum) ms. » 95 % of all devices are better.
This means that the measured response time is worse than the average of all tested devices (25 ms).
       Response Time 50% Grey to 80% Grey
56 ms ... rise ↗ and fall ↘ combined↗ 31.6 ms rise
↘ 24.4 ms fall
The screen shows slow response rates in our tests and will be unsatisfactory for gamers.
In comparison, all tested devices range from 0.9 (minimum) to 636 (maximum) ms. » 91 % of all devices are better.
This means that the measured response time is worse than the average of all tested devices (39.8 ms).

Screen Flickering / PWM (Pulse-Width Modulation)

To dim the screen, some notebooks will simply cycle the backlight on and off in rapid succession - a method called Pulse Width Modulation (PWM) . This cycling frequency should ideally be undetectable to the human eye. If said frequency is too low, users with sensitive eyes may experience strain or headaches or even notice the flickering altogether.
Screen flickering / PWM detected 1667 Hz ≤ 24 % brightness setting

The display backlight flickers at 1667 Hz (Likely utilizing PWM) Flickering detected at a brightness setting of 24 % and below. There should be no flickering or PWM above this brightness setting.

The frequency of 1667 Hz is quite high, so most users sensitive to PWM should not notice any flickering.

In comparison: 51 % of all tested devices do not use PWM to dim the display. If PWM was detected, an average of 9394 (minimum: 43 - maximum: 142900) Hz was measured.

Unsurprisingly, response times from the screen are slow and unsuitable for competitive gaming—which is not what this laptop is meant to be used for anyway. PWM was detected at very low brightness levels (24% and below), but the frequency of 1.667 KHz is high enough that it shouldn’t bother most sensitive users.

Outdoors, the display struggles and is barely usable in brighter environments. That’s because of the highly reflective finish in conjunction with the below-average brightness. In shaded areas, with tactful positioning, the picture is acceptable. As usual, we’d love to see an anti-glare option, but it’s unlikely.

In the sun
In the sun
In the shade
In the shade
LCD viewing angles
LCD viewing angles

Performance

The Latitude 7400 2-in-1 is configurable with Intel 8th-generation CPUs ranging from the Core i5-8265U all the way up to the i7-8665U. Either 8 GB or 16 GB of LPDDR3 RAM can be selected—but it’s important to note that the RAM cannot be upgraded post-purchase thanks to the fact that it’s soldered to the mainboard, so be sure to get what you need from the start. Storage device options are 100% comprised of M.2 NVMe solid-state drives, ranging in capacity from 128 GB up to 1 TB (and Dell promises eventually, later this summer, up to 2 TB). Our review unit came outfitted with the highest-end Core i7-8665U SoC, 16 GB of LPDDR3 RAM, and a 512 GB NVMe SSD.

LatencyMon detects some pretty immediate spikes in DPC Latencies on the machine; these persist regardless of the state of the wireless radios (WLAN, Bluetooth). It is possible that a driver update elsewhere might resolve this in the future.

CPU-Z CPU
CPU-Z CPU
CPU-Z Caches
CPU-Z Caches
CPU-Z Mainboard
CPU-Z Mainboard
CPU-Z Memory
CPU-Z Memory
GPU-Z
GPU-Z
HWiNFO
HWiNFO
Geekbench 4.1
Geekbench 4.1
LatencyMon
LatencyMon

Processor

The Intel Core i7-8665U SoC is the newest addition to the eighth-gen Intel lineup, announced in April 2019. It’s a Whiskey Lake generation chip manufactured using an improved 14 nm process (14 nm++) and offering very high potential Turbo boost rates of up to 4.8 GHz. The latter is due to a new feature called Thermal Velocity Boost, which, as Intel puts it, “opportunistically and automatically increase[s] core frequency whenever processor temperature and turbo budget allows.”

If that sounds an awful lot like Turbo Boost, that’s because it is—but it’s more sensitive to system parameters, not unlike (for instance) NVIDIA’s Max-Q design... but sort of in reverse, if you will. Basically, it allows for a short-term increase of CPU clock rate by up to a few hundred MHz on top of Turbo Boost provided the requisite conditions are in play. The theory is that this should lead to a snappier user experience, since most everyday workloads consist of short-term burst sequences anyway.

The i7-8665U is configured for a theoretical absolute maximum clock rate of 4.8 GHz under this new TVB functionality. Elsewhere, the numbers remain the same: it still carries a 15 W TDP and is paired with Intel UHD Graphics 620 @ 300 – 1150 MHz. This is the first chance we’ve had to test the i7-8665U, but we should expect performance hopefully exceeding that of the Core i7-8565U, since hypothetically the clock rate should be able to reach 200 MHz higher limits if conditions are ideal.

Cinebench R15
CPU Single 64Bit
Average Intel Core i7-8665U
  (176 - 199, n=5)
184 Points ∼84% +5%
Lenovo ThinkPad E590-20NB0012GE
Intel Core i7-8565U
181 Points ∼83% +3%
Dell Latitude 7490
Intel Core i7-8650U
176 Points ∼81% 0%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
176 Points ∼81%
HP Elitebook x360 1040 G5
Intel Core i7-8650U
172 Points ∼79% -2%
Lenovo ThinkPad T480s-20L8S02E00
Intel Core i7-8550U
170 Points ∼78% -3%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel Core i7-8550U
168 Points ∼77% -5%
Lenovo ThinkPad T480-20L6S01V00
Intel Core i7-8550U
161 Points ∼74% -9%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
158 Points ∼72% -10%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel Core i5-8350U
150 Points ∼69% -15%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
149 Points ∼68% -15%
Dell Latitude 14 5495
AMD Ryzen 7 2700U
148 Points ∼68% -16%
Asus ZenBook Flip 14 UX461UA
Intel Core i5-8250U
144 Points ∼66% -18%
HP Pavilion x360 14-cd0002ng
Intel Core i3-8130U
139 Points ∼64% -21%
Average of class Convertible
  (19 - 179, n=296)
105 Points ∼48% -40%
CPU Multi 64Bit
Lenovo ThinkPad T480s-20L8S02E00
Intel Core i7-8550U
723 Points ∼17% +38%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel Core i7-8550U
699 Points ∼16% +33%
Dell Latitude 14 5495
AMD Ryzen 7 2700U
670 Points ∼15% +28%
Lenovo ThinkPad T480-20L6S01V00
Intel Core i7-8550U
657 Points ∼15% +25%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
654 Points ∼15% +25%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
647 Points ∼15% +23%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel Core i5-8350U
631 Points ∼14% +20%
Average Intel Core i7-8665U
  (524 - 701, n=5)
624 Points ∼14% +19%
Dell Latitude 7490
Intel Core i7-8650U
618 Points ∼14% +18%
Asus ZenBook Flip 14 UX461UA
Intel Core i5-8250U
558 Points ∼13% +6%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
550 Points ∼13% +5%
HP Elitebook x360 1040 G5
Intel Core i7-8650U
534 Points ∼12% +2%
Lenovo ThinkPad E590-20NB0012GE
Intel Core i7-8565U
527 Points ∼12% +1%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
524 Points ∼12%
HP Pavilion x360 14-cd0002ng
Intel Core i3-8130U
320 Points ∼7% -39%
Average of class Convertible
  (33 - 761, n=303)
294 Points ∼7% -44%
Cinebench R11.5
CPU Single 64Bit
Dell Latitude 7490
Intel Core i7-8650U
2.01 Points ∼82% +20%
Lenovo ThinkPad T480s-20L8S02E00
Intel Core i7-8550U
1.94 Points ∼80% +16%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
1.93 Points ∼79% +16%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
1.73 Points ∼71% +4%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
1.67 Points ∼68%
Average Intel Core i7-8665U
 
1.67 Points ∼68% 0%
Asus ZenBook Flip 14 UX461UA
Intel Core i5-8250U
1.65 Points ∼68% -1%
Lenovo ThinkPad T480-20L6S01V00
Intel Core i7-8550U
1.43 Points ∼59% -14%
Average of class Convertible
  (0.24 - 2.01, n=219)
1.123 Points ∼46% -33%
CPU Multi 64Bit
Lenovo ThinkPad T480s-20L8S02E00
Intel Core i7-8550U
7.84 Points ∼23% +61%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
7.22 Points ∼22% +48%
Dell Latitude 7490
Intel Core i7-8650U
6.96 Points ∼21% +43%
Lenovo ThinkPad T480-20L6S01V00
Intel Core i7-8550U
6.92 Points ∼21% +42%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
5.94 Points ∼18% +22%
Asus ZenBook Flip 14 UX461UA
Intel Core i5-8250U
5.93 Points ∼18% +22%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
4.88 Points ∼15%
Average Intel Core i7-8665U
 
4.88 Points ∼15% 0%
Average of class Convertible
  (0.45 - 8.56, n=228)
2.82 Points ∼8% -42%
Cinebench R10
Rendering Single 32Bit
Lenovo ThinkPad E590-20NB0012GE
Intel Core i7-8565U
6968 Points ∼64% +4%
Average Intel Core i7-8665U
  (6716 - 7028, n=2)
6872 Points ∼63% +2%
Dell Latitude 7490
Intel Core i7-8650U
6727 Points ∼62% 0%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
6716 Points ∼62%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
6648 Points ∼61% -1%
Lenovo ThinkPad T480s-20L8S02E00
Intel Core i7-8550U
6437 Points ∼59% -4%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
5841 Points ∼54% -13%
Asus ZenBook Flip 14 UX461UA
Intel Core i5-8250U
5523 Points ∼51% -18%
Average of class Convertible
  (466 - 7508, n=241)
3368 Points ∼31% -50%
Rendering Multiple CPUs 32Bit
Lenovo ThinkPad T480s-20L8S02E00
Intel Core i7-8550U
22188 Points ∼45% +34%
Dell Latitude 7490
Intel Core i7-8650U
20349 Points ∼41% +23%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
20179 Points ∼41% +22%
Average Intel Core i7-8665U
  (16602 - 20251, n=2)
18427 Points ∼37% +11%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
17276 Points ∼35% +4%
Lenovo ThinkPad E590-20NB0012GE
Intel Core i7-8565U
16725 Points ∼34% +1%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
16602 Points ∼33%
Asus ZenBook Flip 14 UX461UA
Intel Core i5-8250U
15292 Points ∼31% -8%
Average of class Convertible
  (706 - 24180, n=237)
7765 Points ∼16% -53%
wPrime 2.0x - 1024m
Average of class Convertible
  (245 - 3227, n=113)
810 s * ∼10% -89%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
429.319 s * ∼5%
Average Intel Core i7-8665U
 
429 s * ∼5% -0%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
371.408 s * ∼4% +13%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
277.395 s * ∼3% +35%
Super Pi Mod 1.5 XS 32M - ---
Average Intel Core i7-8665U
  (8 - 6528, n=5)
2656 Seconds * ∼12% -410%
Average of class Convertible
  (0.046 - 64540, n=1373)
1580 Seconds * ∼7% -203%
Asus Zenbook 14 UX433FA-A6018T
Intel Core i5-8265U
590.085 Seconds * ∼3% -13%
Dell Inspiron 14 5000 5482 2-in-1
Intel Core i7-8565U
582.988 Seconds * ∼3% -12%
Dell Latitude 7400 2-in-1
Intel Core i7-8665U
521 Seconds * ∼2%

* ... smaller is better

The single-threaded wPrime 2.0 1024m benchmark finishes in 429 s, which is 55% longer than the Dell Inspiron 14 5000 2-in-1 took to complete. Cooldowns make very little difference here thanks to the lengthy duration of the benchmark, which helps to average out the wrinkles statistically speaking. No matter how you slice it, the problem with the Latitude’s CPU performance is clearly confined to sustained load situations—and in particular, those lasting longer than several seconds and, equally importantly, separated by cooldown periods of shorter than a few minutes apiece. Sure, it’s a quiet machine, but at the great expense of its overall processing capability and, as we’ll see later, also its surface temperatures.

Cinebench R10 Shading 32Bit
9678
Cinebench R10 Rendering Multiple CPUs 32Bit
16602
Cinebench R10 Rendering Single 32Bit
6716
Cinebench R11.5 CPU Multi 64Bit
4.88 Points
Cinebench R11.5 OpenGL 64Bit
33.63 fps
Cinebench R11.5 CPU Single 64Bit
1.67 Points
Cinebench R15 CPU Single 64Bit
176 Points
Cinebench R15 Ref. Match 64Bit
97.8 %
Cinebench R15 OpenGL 64Bit
54.01 fps
Cinebench R15 CPU Multi 64Bit
524 Points
Help

Our Cinebench R15 multi-CPU loop test helps to visualize the challenges the laptop faces with sustained computing loads. Even in the initial runs, performance is below many lesser-equipped competitors, such as the Asus Zenbook 14 (i5-8265U) and Dell Latitude 7490 (i7-8650U). After the first several runs, however, performance plummets even further toward territory occupied by the Zenbook Flip (i5-8250U) and ThinkPad X1 Carbon G6 (i5-8350U).

None of this is to say that the Latitude 7400’s performance is bad—just that it’s disappointing given the SoC’s pedigree and the performance of related Core i5 variants. It’s been a lengthy analysis, but in conclusion: we’d recommend that you absolutely skip the Core i7 options for this machine. Quite clearly, we can’t expect them to perform much (or any) better than their lower-end and considerably more affordable counterparts.

September 2, 2019 update: The i5-8265U is the entry point into the world of Latitude 7000 convertibles. This configuration of the device can be purchased for as little as 1,500 Euros and includes a 512 GB SSD. Since the features are otherwise identical, the high premium for a Core i7 is questionable. How big is the performance discrepancy in reality? Is the Core i5 able to work together more efficiently with the cooling solution? In CineBench's R15 Multi-Thread test, the Core i7 only beats the i5-8265U by 15%. In the R15 Single-Thread test, the difference is only 11%. The base clock of the i5-8265U is 1,600 MHz, while single cores can reach a frequency of up to 3,900 MHz. This also works in real-world scenarios, with a single core running at 3,800 MHz during CineBench's single-thread test. The multi-thread test paints another picture, of course and here, the cores run at 2,300 MHz. These values lie comfortably within the Turbo Boost clock range.

Under prolonged stress, the difference between Core i5 and i7 is only 75 points, with 475 and 550 points, respectively, for the two Latitude 7400 variants during the R15 loop. While the Core i7's performance already drops by 9% after the first loop, the i5 does not throttle at all and even performs marginally faster in the second loop. See also our R15 loop comparison, where the results from both of the Latitude SKUs are listed one after the other.

In conclusion, our previous observations still stand: A Core i7 is definitely not worth the high premium, since an i5 is almost as fast with no throttling under load.

In other words: The Core i5 does not overpower the cooling solution. Our R15 log file also confirms this: While the clock speed is at 2,3 GHz on average, the core temperature consistently stays at just below 90 °C.

0102030405060708090100110120130140150160170180190200210220230240250260270280290300310320330340350360370380390400410420430440450460470480490500510520530540550560570580590600610620630640650660670680Tooltip
Lenovo ThinkPad X1 Carbon G6-20KG0025UK UHD Graphics 620, 8350U, Lenovo LENSE20256GMSP34MEAT2TA; CPU Single 64Bit: Ø480 (455.19-630.99)
Dell Latitude 7400 2-in-1 UHD Graphics 620, 8665U, Toshiba XG6 KXG60ZNV512G; CPU Multi 64Bit: Ø550 (527.93-598.95)
Dell Latitude 7400 2-in-1 i5-8265U UHD Graphics 620, 8265U; CPU Multi 64Bit: Ø472 (457.73-474.6)
Lenovo ThinkPad X1 Yoga 2018-20LES01W00 UHD Graphics 620, 8550U, Samsung SSD PM981 MZVLB512HAJQ; CPU Multi 64Bit: Ø607 (551.32-678.21)
Asus ZenBook Flip 14 UX461UA UHD Graphics 620, 8250U, SanDisk SD8SN8U256G1002; CPU Multi 64Bit: Ø514 (499.85-558.16)
HP Elitebook x360 1040 G5 UHD Graphics 620, 8650U, Samsung SSD PM981 MZVLB512HAJQ; CPU Multi 64Bit: Ø525 (511.81-563.88)
Dell Latitude 7490 UHD Graphics 620, 8650U, Samsung PM961 MZVLW256HEHP; CPU Multi 64Bit: Ø583 (509.4-665.68)
Asus Zenbook 14 UX433FA-A6018T UHD Graphics 620, 8265U, WDC PC SN520 SDAPNUW-256G; CPU Multi 64Bit: Ø504 (494.08-654.12)
Asus Zenbook 14 UX433FA-A6018T UHD Graphics 620, 8265U, WDC PC SN520 SDAPNUW-256G; CPU Multi 64Bit; BIOS 204: Ø571 (557.17-647.21)
Dell Latitude 14 5495 Vega 10, 2700U, Intel SSDSCKKF256G8; CPU Multi 64Bit: Ø620 (605-670)

Please note: After our initial testing had been completed, we reinstalled the Dell Power Manager software and switched the thermal profile from Optimized to Ultra Performance. Although Ultra Performance warns of higher possible surface temperatures, we didn’t notice this in the case of our review unit. However, what we did witness was stronger sustained performance from certain CPU benchmarks against a backdrop of slightly higher noise levels. The problem is that the results, while better on the average, were still far from consistent. One run would produce values consistently above 500, whereas the next would fluctuate between ~520 and ~480. This is still better than our initial run on the default Optimized profile, but it’s far from a silver bullet. Cooldown periods did not seem to make a difference here.

Our test results remain focused on the initial, default values against which temperature and noise levels were measured as well, but it’s worth noting that if you’re considering investing in this machine, immediately updating Power Manager and switching to Ultra Performance permanently could help to at least mitigate some of the performance constraints we reference in this review.

Apart from the separate secondary Cinebench R15 loop results we display below, other benchmarks improved slightly as well. For example, wPrime 1024m completion time dropped marginally to 411 seconds (from 429), an improvement of 4%. There was no statistical difference in single-core or shorter-term benchmarks such as Super Pi.

System Performance

What does all of this mean for overall system performance though? The Latitude 7400 2-in-1 is performing where we'd expect it to be given the CPU. PCMark 10 provides an overall score of 4060 points, which is in line with the the EliteBook x360 1040 G5 and slightly above the w the ThinkPad X1 Yoga. PCMark 8 returns similar results against the competing machines apart from last year’s Latitude 7490 (which leads by 9%).

(June 6, 2019 update: Reran PCMark 10 with the new results included below. Scores are now in line with what we were expecting based on the CPU and notebook category.)

September 2, 2019 update: We once again ran PCMark 10 on the i5 SKU and added our new findings to the test results below. While the overall score of the i5 is 10 % lower than that of the Core i7, the i5 barely manages to outperform the i7 in the digital content creation benchmark.

PCMark 10
PCMark 10
PCMark 8 Home Accelerated
PCMark 8 Home Accelerated
PCMark 8 Work Accelerated
PCMark 8 Work Accelerated
i5-8265U - PCMark 10
i5-8265U - PCMark 10
 
 
PCMark 10
Digital Content Creation
Average Intel Core i7-8665U, Intel UHD Graphics 620
  (2859 - 3506, n=5)
3118 Points ∼26% +9%
HP Elitebook x360 1040 G5
UHD Graphics 620, 8650U, Samsung SSD PM981 MZVLB512HAJQ
3069 Points ∼26% +7%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
UHD Graphics 620, 8350U, Lenovo LENSE20256GMSP34MEAT2TA
3024 Points ∼25% +6%
Dell Latitude 7400 2-in-1
UHD Graphics 620, 8665U, Toshiba XG6 KXG60ZNV512G
2859 Points ∼24%
Asus ZenBook Flip 14 UX461UA
UHD Graphics 620, 8250U, SanDisk SD8SN8U256G1002
2739 Points ∼23% -4%
Average of class Convertible
  (605 - 4342, n=95)
2469 Points ∼21% -14%
HP Pavilion x360 14-cd0002ng
UHD Graphics 620, 8130U, Toshiba KBG30ZMV256G
2232 Points ∼19% -22%
Dell Latitude 7490
UHD Graphics 620, 8650U, Samsung PM961 MZVLW256HEHP
2117 Points ∼18% -26%
Productivity
Average Intel Core i7-8665U, Intel UHD Graphics 620
  (6870 - 7281, n=5)
7084 Points ∼73% 0%
Dell Latitude 7400 2-in-1
UHD Graphics 620, 8665U, Toshiba XG6 KXG60ZNV512G
7077 Points ∼73%
HP Elitebook x360 1040 G5
UHD Graphics 620, 8650U, Samsung SSD PM981 MZVLB512HAJQ
6670 Points ∼69% -6%
Dell Latitude 7490
UHD Graphics 620, 8650U, Samsung PM961 MZVLW256HEHP
6521 Points ∼67% -8%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
UHD Graphics 620, 8350U, Lenovo LENSE20256GMSP34MEAT2TA
6140 Points ∼63% -13%
Asus ZenBook Flip 14 UX461UA
UHD Graphics 620, 8250U, SanDisk SD8SN8U256G1002
5830 Points ∼60% -18%
HP Pavilion x360 14-cd0002ng
UHD Graphics 620, 8130U, Toshiba KBG30ZMV256G
5525 Points ∼57% -22%
Average of class Convertible
  (1121 - 7077, n=97)
5249 Points ∼54% -26%
Essentials
HP Elitebook x360 1040 G5
UHD Graphics 620, 8650U, Samsung SSD PM981 MZVLB512HAJQ
8992 Points ∼82% 0%
Dell Latitude 7400 2-in-1
UHD Graphics 620, 8665U, Toshiba XG6 KXG60ZNV512G
8980 Points ∼82%
Average Intel Core i7-8665U, Intel UHD Graphics 620
  (8199 - 9790, n=5)
8978 Points ∼82% 0%
Dell Latitude 7490
UHD Graphics 620, 8650U, Samsung PM961 MZVLW256HEHP
7929 Points ∼72% -12%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
UHD Graphics 620, 8350U, Lenovo LENSE20256GMSP34MEAT2TA
7799 Points ∼71% -13%
Asus ZenBook Flip 14 UX461UA
UHD Graphics 620, 8250U, SanDisk SD8SN8U256G1002
7124 Points ∼65% -21%
Average of class Convertible
  (2489 - 9291, n=97)
6924 Points ∼63% -23%
HP Pavilion x360 14-cd0002ng
UHD Graphics 620, 8130U, Toshiba KBG30ZMV256G
6902 Points ∼63% -23%
Score
Average Intel Core i7-8665U, Intel UHD Graphics 620
  (4005 - 4515, n=5)
4176 Points ∼54% +3%
HP Elitebook x360 1040 G5
UHD Graphics 620, 8650U, Samsung SSD PM981 MZVLB512HAJQ
4078 Points ∼53% 0%
Dell Latitude 7400 2-in-1
UHD Graphics 620, 8665U, Toshiba XG6 KXG60ZNV512G
4060 Points ∼52%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
UHD Graphics 620, 8550U, Samsung SSD PM981 MZVLB512HAJQ
3829 Points ∼49% -6%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
UHD Graphics 620, 8350U, Lenovo LENSE20256GMSP34MEAT2TA
3764 Points ∼48% -7%
Asus ZenBook Flip 14 UX461UA
UHD Graphics 620, 8250U, SanDisk SD8SN8U256G1002
3473 Points ∼45% -14%
Dell Latitude 7490
UHD Graphics 620, 8650U, Samsung PM961 MZVLW256HEHP
3429 Points ∼44% -16%
Average of class Convertible
  (872 - 4347, n=98)
3159 Points ∼41% -22%
HP Pavilion x360 14-cd0002ng
UHD Graphics 620, 8130U, Toshiba KBG30ZMV256G
3153 Points ∼41% -22%
PCMark 8
Work Score Accelerated v2
Dell Latitude 7490
UHD Graphics 620, 8650U, Samsung PM961 MZVLW256HEHP
5155 Points ∼79% +9%
Average Intel Core i7-8665U, Intel UHD Graphics 620
  (4696 - 5195, n=4)
4932 Points ∼76% +4%
Dell Latitude 7400 2-in-1
UHD Graphics 620, 8665U, Toshiba XG6 KXG60ZNV512G
4743 Points ∼73%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
UHD Graphics 620, 8550U, Samsung SSD PM981 MZVLB512HAJQ
4719 Points ∼72% -1%
Asus ZenBook Flip 14 UX461UA
UHD Graphics 620, 8250U, SanDisk SD8SN8U256G1002
4700 Points ∼72% -1%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
UHD Graphics 620, 8350U, Lenovo LENSE20256GMSP34MEAT2TA
4600 Points ∼71% -3%
HP Elitebook x360 1040 G5
UHD Graphics 620, 8650U, Samsung SSD PM981 MZVLB512HAJQ
4558 Points ∼70% -4%
HP Pavilion x360 14-cd0002ng
UHD Graphics 620, 8130U, Toshiba KBG30ZMV256G
4412 Points ∼68% -7%
Average of class Convertible
  (1007 - 5281, n=226)
3725 Points ∼57% -21%
Home Score Accelerated v2
Dell Latitude 7490
UHD Graphics 620, 8650U, Samsung PM961 MZVLW256HEHP
4029 Points ∼66% +13%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
UHD Graphics 620, 8550U, Samsung SSD PM981 MZVLB512HAJQ
3824 Points ∼63% +8%
Average Intel Core i7-8665U, Intel UHD Graphics 620
  (3547 - 4211, n=5)
3818 Points ∼63% +8%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
UHD Graphics 620, 8350U, Lenovo LENSE20256GMSP34MEAT2TA
3690 Points ∼61% +4%
Asus ZenBook Flip 14 UX461UA
UHD Graphics 620, 8250U, SanDisk SD8SN8U256G1002
3660 Points ∼60% +3%
Dell Latitude 7400 2-in-1
UHD Graphics 620, 8665U, Toshiba XG6 KXG60ZNV512G
3550 Points ∼58%
HP Elitebook x360 1040 G5
UHD Graphics 620, 8650U, Samsung SSD PM981 MZVLB512HAJQ
3308 Points ∼54% -7%
HP Pavilion x360 14-cd0002ng
UHD Graphics 620, 8130U, Toshiba KBG30ZMV256G
3198 Points ∼52% -10%
Average of class Convertible
  (741 - 4741, n=274)
2788 Points ∼46% -21%
PCMark 8 Home Score Accelerated v2
3550 points
PCMark 8 Work Score Accelerated v2
4743 points
Help

Storage Devices

As previously mentioned, the Latitude 7400 2-in-1 can be equipped with an array of NVMe solid-state drives from the factory ranging in capacity from 256 GB up to 1 TB (and, soon, 2 TB). Our review unit includes a 512 GB Toshiba KXG60ZNV512G M.2 NVMe SSD, which is a new model in our testing database that we’ve not yet evaluated.

Sequential speeds from the SSD are very good, with AS SSD turning in 2288 MB/s and 1163 MB/s in the seq read/write tests respectively. 4K QD32 performance, however, is well below the PM981 (which powers the HP EliteBook x360)—and so that will have a bearing on overall perceived system performance.

The drive is relatively easy to access and replace, so if users wish to choose a lower capacity option and upgrade aftermarket to the drive of their choice, it shouldn’t be too much of a hassle.

AS SSD
AS SSD
CrystalDiskMark
CrystalDiskMark
Dell Latitude 7400 2-in-1
Toshiba XG6 KXG60ZNV512G
Asus ZenBook Flip 14 UX461UA
SanDisk SD8SN8U256G1002
HP Elitebook x360 1040 G5
Samsung SSD PM981 MZVLB512HAJQ
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Lenovo LENSE20256GMSP34MEAT2TA
AS SSD
-27%
136%
29%
Copy Game MB/s
1055.12
186.06
-82%
1024.32
-3%
Copy Program MB/s
379.42
118.61
-69%
450.29
19%
Copy ISO MB/s
1767.39
324.09
-82%
2034.38
15%
Score Total
1300
908
-30%
3790
192%
1443
11%
Score Write
345
236
-32%
1440
317%
405
17%
Score Read
667
441
-34%
1569
135%
718
8%
Access Time Write *
0.143
0.086
40%
0.035
76%
0.144
-1%
Access Time Read *
0.122
0.123
-1%
0.043
65%
0.108
11%
4K-64 Write
199.5
146.36
-27%
1208.83
506%
195.84
-2%
4K-64 Read
415.58
368.32
-11%
1341.64
223%
446.09
7%
4K Write
28.92
50.7
75%
104.06
260%
87.56
203%
4K Read
22.29
26.93
21%
46.25
107%
35.67
60%
Seq Write
1162.98
388.17
-67%
1269.89
9%
1219.53
5%
Seq Read
2288.68
459.86
-80%
1815.96
-21%
2364.51
3%
CrystalDiskMark 5.2 / 6
30%
168%
122%
Write 4K
35.06
52.4
49%
122.7
250%
116.4
232%
Read 4K
23.64
27.91
18%
46.57
97%
45.75
94%
Write Seq
1537
428.2
-72%
1725
12%
455.1
-70%
Read Seq
1782
435.9
-76%
2392
34%
1818
2%
Write 4K Q32T1
100.3
246
145%
470.6
369%
248.9
148%
Read 4K Q32T1
62.73
255.6
307%
313.2
399%
358
471%
Write Seq Q32T1
2698
455.6
-83%
1869
-31%
1191
-56%
Read Seq Q32T1
1073
554.3
-48%
3380
215%
2755
157%
Total Average (Program / Settings)
2% / -6%
152% / 148%
76% / 68%

* ... smaller is better

Toshiba XG6 KXG60ZNV512G
CDM 5/6 Read Seq Q32T1: 1073 MB/s
CDM 5/6 Write Seq Q32T1: 2698 MB/s
CDM 5/6 Read 4K Q32T1: 62.73 MB/s
CDM 5/6 Write 4K Q32T1: 100.3 MB/s
CDM 5 Read Seq: 1782 MB/s
CDM 5 Write Seq: 1537 MB/s
CDM 5/6 Read 4K: 23.64 MB/s
CDM 5/6 Write 4K: 35.06 MB/s

GPU Performance

The Latitude is powered by integrated Intel UHD Graphics 620, which is fine for everyday office use and battery-friendly, to boot. While GPU performance remains acceptable, no real gains have been made over the Core i7-8550U/i5-8350U crowd. 3DMark Fire Strike turns in a score of 1245 points, just 3% below the Lenovo X1 Yoga’s 1288 (i7-8550U) and the X1 Carbon’s 1283 (i5-8350U). Results are somewhat more pronounced in the Cloud Gate and 3DMark 11 Graphics benchmarks (see below), with margins widening to the 6 to 7 percentage points mark. Of course, in the case of combined and overall scores, where CPU performance is also taken heavily into account, the 7400 struggles quite a bit more.

Graphical performance is sufficient to run only basic and older games at lower settings smoothly. Especially with its thermal limitations, the Latitude 7400 2-in-1 is not meant to be used for gaming.

3DMark Fire Strike
3DMark Fire Strike
3DMark Cloud Gate
3DMark Cloud Gate
3DMark 11
3DMark 11
3DMark 06
3DMark 06
3DMark 11
1280x720 Performance Combined
Lenovo ThinkPad E590-20NB0012GE
AMD Radeon RX 550X (Laptop), 8565U
4957 Points ∼22% +220%
Lenovo ThinkPad T480-20L6S01V00
NVIDIA GeForce MX150, 8550U
4211 Points ∼19% +172%
Lenovo ThinkPad T480s-20L8S02E00
NVIDIA GeForce MX150, 8550U
3547 Points ∼16% +129%
Dell Latitude 14 5495
AMD Radeon RX Vega 10, 2700U
1945 Points ∼9% +25%
HP Elitebook x360 1040 G5
Intel UHD Graphics 620, 8650U
1869 Points ∼8% +21%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel UHD Graphics 620, 8550U
1752 Points ∼8% +13%
Asus ZenBook Flip 14 UX461UA
Intel UHD Graphics 620, 8250U
1669 Points ∼7% +8%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel UHD Graphics 620, 8350U
1632 Points ∼7% +5%
Dell Latitude 7400 2-in-1
Intel UHD Graphics 620, 8665U
1550 Points ∼7%
Average Intel UHD Graphics 620
  (959 - 2084, n=165)
1540 Points ∼7% -1%
HP Pavilion x360 14-cd0002ng
Intel UHD Graphics 620, 8130U
1193 Points ∼5% -23%
Average of class Convertible
  (204 - 7304, n=324)
1135 Points ∼5% -27%
1280x720 Performance GPU
Lenovo ThinkPad E590-20NB0012GE
AMD Radeon RX 550X (Laptop), 8565U
5332 Points ∼10% +200%
Lenovo ThinkPad T480-20L6S01V00
NVIDIA GeForce MX150, 8550U
4300 Points ∼8% +142%
Lenovo ThinkPad T480s-20L8S02E00
NVIDIA GeForce MX150, 8550U
3551 Points ∼7% +100%
Dell Latitude 14 5495
AMD Radeon RX Vega 10, 2700U
3080 Points ∼6% +73%
HP Elitebook x360 1040 G5
Intel UHD Graphics 620, 8650U
1902 Points ∼4% +7%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel UHD Graphics 620, 8550U
1869 Points ∼4% +5%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel UHD Graphics 620, 8350U
1868 Points ∼4% +5%
Dell Latitude 7400 2-in-1
Intel UHD Graphics 620, 8665U
1778 Points ∼3%
Asus ZenBook Flip 14 UX461UA
Intel UHD Graphics 620, 8250U
1764 Points ∼3% -1%
Average Intel UHD Graphics 620
  (1235 - 2006, n=165)
1716 Points ∼3% -3%
HP Pavilion x360 14-cd0002ng
Intel UHD Graphics 620, 8130U
1451 Points ∼3% -18%
Average of class Convertible
  (173 - 7483, n=325)
1243 Points ∼2% -30%
3DMark
2560x1440 Time Spy Graphics
Lenovo ThinkPad E590-20NB0012GE
AMD Radeon RX 550X (Laptop), 8565U
1051 Points ∼7%
Average of class Convertible
  (85 - 1682, n=29)
455 Points ∼3%
Asus ZenBook Flip 14 UX461UA
Intel UHD Graphics 620, 8250U
364 Points ∼3%
Average Intel UHD Graphics 620
  (299 - 431, n=29)
356 Points ∼2%
1920x1080 Fire Strike Graphics
Lenovo ThinkPad E590-20NB0012GE
AMD Radeon RX 550X (Laptop), 8565U
3678 Points ∼9% +195%
Lenovo ThinkPad T480-20L6S01V00
NVIDIA GeForce MX150, 8550U
3585 Points ∼9% +188%
Lenovo ThinkPad T480s-20L8S02E00
NVIDIA GeForce MX150, 8550U
2807 Points ∼7% +125%
Dell Latitude 14 5495
AMD Radeon RX Vega 10, 2700U
1835 Points ∼5% +47%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel UHD Graphics 620, 8550U
1288 Points ∼3% +3%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel UHD Graphics 620, 8350U
1283 Points ∼3% +3%
Dell Latitude 7400 2-in-1
Intel UHD Graphics 620, 8665U
1245 Points ∼3%
Asus ZenBook Flip 14 UX461UA
Intel UHD Graphics 620, 8250U
1180 Points ∼3% -5%
Dell Latitude 7490
Intel UHD Graphics 620, 8650U
1163 Points ∼3% -7%
Average Intel UHD Graphics 620
  (557 - 1401, n=134)
1127 Points ∼3% -9%
Average of class Convertible
  (132 - 5965, n=233)
994 Points ∼2% -20%
1280x720 Cloud Gate Standard Graphics
Lenovo ThinkPad T480-20L6S01V00
NVIDIA GeForce MX150, 8550U
21893 Points ∼12% +115%
Lenovo ThinkPad E590-20NB0012GE
AMD Radeon RX 550X (Laptop), 8565U
19931 Points ∼11% +96%
Lenovo ThinkPad T480s-20L8S02E00
NVIDIA GeForce MX150, 8550U
17743 Points ∼10% +75%
HP Elitebook x360 1040 G5
Intel UHD Graphics 620, 8650U
10804 Points ∼6% +6%
Dell Latitude 14 5495
AMD Radeon RX Vega 10, 2700U
10773 Points ∼6% +6%
Lenovo ThinkPad X1 Yoga 2018-20LES01W00
Intel UHD Graphics 620, 8550U
10493 Points ∼6% +3%
Lenovo ThinkPad X1 Carbon G6-20KG0025UK
Intel UHD Graphics 620, 8350U
10234 Points ∼6% +1%
Dell Latitude 7400 2-in-1
Intel UHD Graphics 620, 8665U
10165 Points ∼6%
Dell Latitude 7490
Intel UHD Graphics 620, 8650U
9730 Points ∼5% -4%
Asus ZenBook Flip 14 UX461UA
Intel UHD Graphics 620, 8250U
9214 Points ∼5% -9%
Average Intel UHD Graphics 620
  (6910 - 11436, n=152)
9153 Points ∼5% -10%
HP Pavilion x360 14-cd0002ng
Intel UHD Graphics 620, 8130U
7357 Points ∼4% -28%
Average of class Convertible
  (1023 - 37388, n=286)
6660 Points ∼4% -34%
1920x1080 Ice Storm Extreme Graphics
Asus ZenBook Flip 14 UX461UA
Intel UHD Graphics 620, 8250U
49254 Points ∼7%
Lenovo ThinkPad E590-20NB0012GE
AMD Radeon RX 550X (Laptop), 8565U
45271 Points ∼6%
Average Intel UHD Graphics 620
  (29002 - 59483, n=37)
44090 Points ∼6%
Average of class Convertible
  (1618 - 81315, n=72)
36514 Points ∼5%
3DMark 06 Standard
10985 points
3DMark 11 Performance
1964 points
3DMark Cloud Gate Standard Score
8781 points
3DMark Fire Strike Score
1133 points
Help
low med. high ultra
BioShock Infinite (2013) 56342817fps

Emissions

System Noise

Is it quiet? Absolutely. The laptop is completely silent while idling, and we measured only a tiny increase over environmental noise levels—28.8 dB(A) versus 28.2 dB(A)—under load. Given the high chip temperatures that we’ll witness the fruits of in the next section, this suggests heavily (low) noise-biased firmware balancing.

Adjusting the settings in the Dell Power Manager application doesn’t seem to affect this much either; although slightly more fan noise is noticeable under the "Cool" and "Ultra Performance" profiles, it's not really that noticeable in general use. CPU clock rates can be artificially/electively limited by choosing the “Cool” profile, which keeps the case cooler overall (and which you’ll probably find yourself using if you’re planning on traveling with the machine and using it lap-borne). We feel like a firmware update from Dell to increase fan RPMs at lower temperature thresholds on the default “Optimized” setting could help to balance this out a bit better. While low noise levels are nice, it’s preferable to be able to choose when they’re prioritized, especially when the inherent bias is affecting surface temperatures and performance so severely in practice.

There is a bit of electrical noise from the charging port area while the machine is on AC power, but it’s only noticeable at pretty close range and it manifests primarily as a muted static of sorts. Most people probably won’t find it bothersome except in the quietest of environments.

September 2, 2019 update: Our impression of the i5 mode's fan behavior is positive through and through. On the ultra performance setting, the fan spins with consistent speeds and creates a subtle background noise. While it does become louder and more noticeable under load, it never becomes distracting. Unlike on our i7, we did not notice any electrical noise coming from the area around the charging port on the i5.

Fan noise profile
Fan noise profile

Noise Level

Idle
28.2 / 28.2 / 28.3 dB(A)
Load
28.2 / 28.8 dB(A)
  red to green bar
 
 
30 dB
silent
40 dB(A)
audible
50 dB(A)
loud
 
min: dark, med: mid, max: light   BK Precision 732A (15 cm distance)   environment noise: 28.2 dB(A)

Temperature

The cooling system is simply overwhelmed by the CPU
The cooling system is simply overwhelmed by the CPU

It’s nothing new, but the Latitude 7400 2-in-1 gets pretty hot under load. Average temperatures aren’t too far from those of the 7490 before it—35.4 °C / 37.6 °C on top/bottom—but that doesn’t tell the whole story. The heat is more heavily concentrated in just a couple of quadrants; whereas before, hot spots on the top and bottom were 45.2 °C / 51.6 °C, now, the temperatures in the hottest quadrants have risen to a blistering 49.6 °C and 60.2 °C. The Dell Power Manager profile selection doesn’t appear to affect this situation much.

Idle temperatures have dropped considerably however. We measure averages only a degree or two above ambient temperatures (21.5 °C / 22 °C on top/bottom) here, which is a big improvement over the previous generation.

Stress Test

Under full CPU stress using Prime95, the Latitude 7400 2-in-1 rockets up to 100 °C CPU temperature within seconds, at which point clock rates drop from roughly 4.2 GHz down to 2.4 GHz, where it remains permanently thereafter. Temperatures at this point remain stable at 89 °C. GPU stress with FurMark results in GPU clock rates of 950 MHz and temperatures at 95 °C.

Combined stress sees a jump up to the 80s °C, after which a slow climb into the 90s °C follows. Throughout this entire stretch, CPU clock rates are pinned at just 1.2 GHz, which is below the base clock rate of the CPU. GPU clock rates slip gradually downward to 700 MHz, where they remain for some time before rebounding to 2.0-2.1 GHz later on.

Running on battery power does not decrease the performance of the system; a secondary run of 3DMark 11 produced a marginally higher score than our original value—2004 versus 1964 in the first run.

(June 7, 2019 update: We reran the Prime95 and FurMark stress tests on a second test unit which produced more stable results than our first test unit. CPU clock rate becomes stable at 2.5 GHz when running Prime95 albeit at a very warm core temperature of over 90 C as shown by our revised screenshots below.)

Full CPU stress using Prime95
Full CPU stress using Prime95
Combined stress
Combined stress

How does the i5-8265U fare in a stress test?

September 2, 2019 update: Prime95 stress is a lot to handle for the i5 and reduces the sustainable clock speeds to 1,700-1,900 MHz on all cores. This is still above the base clock and faster than the i7. The processor only dips below its base clock, if FurMark is run simultaneously in order to stress the integrated graphics card.

Our R15 log file shows: At just below 85 °C, the CPU temperature remains at a decent value, allowing the processor to consistently exceed its base clock.

i5-8265U - Stress test, staggered: 10 min FurMark, 10 min FurMark + Prime95, 10 min Prime95
i5-8265U - Stress test, staggered: 10 min FurMark, 10 min FurMark + Prime95, 10 min Prime95
CPU Clock (GHz) GPU Clock (MHz) Average CPU Temperature (°C) Average GPU Temperature (°C)
Prime95 Stress 2.5 - 2.6 - 96 -
FurMark Stress - 950 - 95
Prime95 + FurMark Stress 0.9 750 86 86
Max. Load
 49.6 °C
121 F
42.4 °C
108 F
30.2 °C
86 F
 
 42.6 °C
109 F
38 °C
100 F
27.8 °C
82 F
 
 33.8 °C
93 F
27.6 °C
82 F
26.8 °C
80 F
 
Maximum: 49.6 °C = 121 F
Average: 35.4 °C = 96 F
29.8 °C
86 F
39 °C
102 F
60.2 °C
140 F
28.6 °C
83 F
38.4 °C
101 F
46 °C
115 F
27.6 °C
82 F
32 °C
90 F
36.4 °C
98 F
Maximum: 60.2 °C = 140 F
Average: 37.6 °C = 100 F
Power Supply (max.)  32.4 °C = 90 F | Room Temperature 20.4 °C = 69 F | Fluke 62 Mini IR Thermometer
(±) The average temperature for the upper side under maximal load is 35.4 °C / 96 F, compared to the average of 30.3 °C / 87 F for the devices in the class Convertible.
(-) The maximum temperature on the upper side is 49.6 °C / 121 F, compared to the average of 35.4 °C / 96 F, ranging from 21.8 to 55.7 °C for the class Convertible.
(-) The bottom heats up to a maximum of 60.2 °C / 140 F, compared to the average of 36.5 °C / 98 F
(+) In idle usage, the average temperature for the upper side is 21.5 °C / 71 F, compared to the device average of 30.3 °C / 87 F.
(+) The palmrests and touchpad are reaching skin temperature as a maximum (33.8 °C / 92.8 F) and are therefore not hot.
(-) The average temperature of the palmrest area of similar devices was 29 °C / 84.2 F (-4.8 °C / -8.6 F).
Thermal profile, top of base unit (idle)
Thermal profile, top of base unit (idle)
Thermal profile, underside (idle)
Thermal profile, underside (idle)
Thermal profile, top of base unit (max load)
Thermal profile, top of base unit (max load)
Thermal profile, side (max load)
Thermal profile, side (max load)
Thermal profile, underside (max load)
Thermal profile, underside (max load)

Speakers

The speakers have been vastly improved over previous models.
The speakers have been vastly improved over previous models.

The speakers have vastly improved over the previous few generations of Dell Latitude 7000-series laptops. One of our major complaints about the Latitude 7490/7390 machines is that the audio system was weak and even just downright bad. Volume levels were low, frequency response was poor, and bass was essentially nonexistent. This wasn’t a deal-breaker because ultimately these are business machines—tools, if you will, first and foremost—but the luxury of higher-quality speakers is still something users appreciate over the life of any machine.

With the Latitude 7400 2-in-1, the speakers have been moved from the bottom front of the machine (where they were previously crammed into a tiny space and couldn’t physically be large enough to result in any sort of reasonably good audio experience) to the sides of the bottom. This allows for larger drivers that produce a much louder volume level. The case materials and reverberation also are leveraged better on this new model for a quality of audio much closer to that of an XPS 15. Low frequencies are still mostly absent, but it isn’t nearly as bad as it was previously. The overall linearity of the sound is now average, with balanced mids and highs and a total result better than 76% of machines we’ve tested.

Speaker sound profile
Speaker sound profile
dB(A) 0102030405060708090Deep BassMiddle BassHigh BassLower RangeMidsHigher MidsLower HighsMid HighsUpper HighsSuper Highs2043.242.643.22539.839.839.83137.438.537.44037.937.437.95038.437.638.46338.935.838.98034.936.334.91003634.13612543.533.743.516053.533.653.520054.332.254.325057.33257.331562.931.662.94006730.86750068.830.468.863068.53068.580068.629.168.6100070.629.170.6125073.628.873.6160074.428.874.4200069.628.369.6250063.128.263.131506628.1664000722872500071.927.971.9630072.527.872.5800069.127.569.11000069.827.669.8125007427.4741600068.127.368.1SPL82.940.882.9N