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Asus AsusPro B551LG-CN009G Notebook Review

Troubled professional. Asus' new Pro laptops are aimed at business professionals - integrating a lot of security features - while also being multimedia powerhouses with a DVD burner and the new GeForce 840M GPU. Unfortunately though, the Taiwanese company has failed to meet its own quality requirements, forcing us to repeat some of the tests with a second Pro B551LG device.
A lot of potential but unfortunately tons of quality issues: The Asus B551LG.
A lot of potential but unfortunately tons of quality issues: The Asus B551LG.

For the original German review, see here.

Having a look at the specs of the device, there's much to fall in love with: A fast Core i7 CPU, a matte Full HD IPS display and the new Nvidia GeForce 840M. Still, this is not just a multimedia laptop, being aimed at "mobile business professionals" (according to Asus). Lots of security features, a docking port, dual-band Wi-Fi, an ergonomic keyboard and Windows 8 (or 7) Pro emphasize this statement. "Professional quality" seems to have been paramount to Asus, as it even mentions on the side of the device that "...it has been built and tested in order to easily exceed common industry standards in terms of quality, sturdiness and reliability." Let us see whether this works out as planned.

Since professional business features and multimedia capabilities are rarely ever combined in one device, none of the other laptops we compare it to are direct competitors. Still, we want to compare the different CPUs, GPUs and mass storage devices. In addition, we want to present two alternatives in the 15.6-inch segment, one of them much more expensive and the other noticeably cheaper than our test device (which costs around 1250 Euros, ~$1707). For 1600 Euros (~$2184), the HP EliteBook 850 G1-H5G44ET with a matte Full HD display (albeit of the TN variety) can be had, including a Intel Core i7-4600U CPU (2x 2.1-3.3 GHz, Hyper-Threading, TDP of 15 watts) which barely differs from that used in the Asus laptop. The HP machine ships with an AMD Radeon HD 8750M, a slim design and a rather low weight of 2 kg, while the Asus Pro weighs 2.5 kg. The last of the three, the Lenovo ThinkPad S540 20B30059GE, weighs 2.1 kg, sporting an Intel Core i5-4200U (2x 1.6-2.6 GHz, Hyper-Threading, TDP of 15 watts) and again a matte TN-based Full HD display. While it costs just 900 Euros (~$1229), it is the only one of these devices shipping with "just" a conventional HDD plus SSD cache instead of an actual SSD. Both the Lenovo and HP laptops ship with a number of security features (fingerprint reader and/or TPM chips plus SmartCard readers) as well.

Case

The chassis has been made from aluminum and plastic, neither leading to a premium impression nor to exceedingly cheap looks. Its boxy, minimalistic shape is quite functional. While the display lid made from matte, black plastic - the same material used for the display frame - reinforced with carbon (according to Asus) may be quite flexible, it is pressure-resistant. A nice change in terms of design is offered by the upper part of the base unit due to its anthracite-colored surface which has been lowered at the location of the keyboard deck, with a (fingerprint-prone) brushed-metal surface in front of that. Luckily, the device is easy to open with just one hand. Plus, the lid doesn't wobble. The base unit shows quite some torsion resistance (due to a magnesium frame inside) without yielding any creaking noises. The fan vents are directly in front of the hinge, making it hard to cover them up. The overall build quality is decent, with some irregularities such as misalignments between the lower and upper parts of the base unit, leading to sharp edges there (see above) which can be felt and seen.

Innards of the Asus Pro B551LG
Innards of the Asus Pro B551LG

The innards are only accessible when the lower part of the base unit is removed. Unfortunately, unscrewing the 19 screws (of differing lengths, which makes it harder to be put back together again) voids the warranty. At least the battery can be replaced without disassembly of the entire device.

The chassis of our test unit was a bit distorted, leading to a "floating" left foot to the front. While this got a bit better over time, it never went away entirely. Luckily, our control device wasn't plagued by this issue.

Connectivity

Lots and lots of ports! Next to the usual ones, a DisplayPort jack and a SmartCard reader have been implemented as well. Even the undead oldie - VGA - is still on board. The DVD burner is placed at the rear end of the right-hand side, thus forcing the remaining ports further to the front (where they might become a nuisance). On the left-hand side, the other ports are spread over the entire length of the device. According to Asus, the device can be connected to the AsusPro Ultra Docking Station via a docking port at the bottom of the device, but we couldn't find any more information about that at the time of writing.

The USB 3.0 port at the rear of the left-hand side sometimes lost its connection to an external USB 3.0 HDD, immediately re-connecting to it in the process. This problem didn't occur with the other USB ports (or other laptops, for that matter). Our second test device didn't come with this peculiarity.

Right-hand side: audio jack, USB 2.0, DVD burner, Kensington lock
Right-hand side: audio jack, USB 2.0, DVD burner, Kensington lock
Left-hand side: power connector, USB 3.0, Ethernet, VGA, DisplayPort, 2x USB 3.0, SmartCard
Left-hand side: power connector, USB 3.0, Ethernet, VGA, DisplayPort, 2x USB 3.0, SmartCard
Front: status LEDs, SD card reader
Front: status LEDs, SD card reader

Communication

Our laptop didn't come with either UMTS or LTE, although such models are supposed to become available in the future. The Intel Wi-Fi module being used is capable of transmitting via the 2.4 and 5 GHz bands (with the usual IEE802.11n standard) as well as via Bluetooth 4.0, but it doesn't offer "Gigabit Wi-Fi" (ac). During our non-standardized real-life test, reception quality was slightly subpar. While two walls and eight meters between the laptop and the router didn't decrease the signal strength, the connection speed decreased a bit faster with distance than for most other laptops which had been tested before.

Security

Asus offers a number of security features: USB blocking via the AsusPro Business Center (pictured), Shockshield HDD protection, a TPM chip (v 1.2), an RF fingerprint reader, a SmartCard slot, HDD encryption, Intel's Anti-Theft technology, Computrace LoJack (remote locking and data deletion as well as localization) and - according to Asus - increased shock protection for the entire device.

Accessories

Next to the warranty sheet, a "user guide" (just a single sheet of paper) and Windows 8 recovery disks, nothing could be found in the box. Care has to be taken to quickly make a recovery copy of the preinstalled Windows 7 version if this is to be used in the foreseeable future.

Warranty

Asus offers 24 months of warranty (as can be seen by a sticker on the back of the device) which holds true all other legal requirements notwithstanding. A warranty extension to up to three years can be had online for around 75 Euros (~$102).

Input Devices

Keyboard

Asus makes use of the not-at-all-slim chassis of its laptop to include an amply sized (and water-resistant!) chiclet-style keyboard with a numpad and nicely long key travel when compared to most laptop keyboards out there. The slim, rubberized keys come with a decent pressure point which is achieved somewhat before rock bottom (in terms of key travel) is reached, leading to a less tiresome typing experience. Another plus: All keys (except for the larger ones) are rather quiet.

Although there is a separate numpad for blindly entering large amounts of data into the system, the numpad is too small, leading to an easy cramping of the right hand when using it for prolonged periods of time, making it harder to type without looking, too. While this may not hold true (after some time) for men and women with smaller hands, the author of this article tried (subconsciously) not to use the numpad too much.

Irritating: The combination "Fn + Wi-Fi" and the combination "Fn + Bluetooth" often didn't work on our device, requiring an actual reboot. Our control device didn't have these issues.

Touchpad

Opponents of the ClickPad currently en vogue will be happy to hear that Asus has decided in favor of a conventional touchpad with separate keys. Its large-enough surface has been roughened slightly, not registering any input close to its edges. The mouse buttons are easy to hit, yielding good haptic feedback and a comfortable level of resistance. Precision and reliability were decent. The Asus Smart Gesture software (pictured) allows the user to comfortably define a number of gestures for up to three fingers. Presumably, for Windows 8 these will include the edge gestures such as the one for the charms menu.

Display

The Asus laptop comes with a Full HD display with an aspect ratio of 16:9, yielding 141 dpi on its 15.6-inches. With this resolution, the "ideal" human eye can still make out single pixels from a distance of half a meter, but in real life, there is nothing to complain about. Even small fonts are rendered in a crisp and sharp manner. The matte surface fits the needs of business professionals while the used IPS technology leads to a good contrast ratio and great viewing-angle stability.

The maximum brightness of 328 cd/m² is quite high, and more than that, it can be sustained even while running on battery (most other laptops fare worse by 15 to 20%). Brightness homogeneity levels of 90% are superb, leading to almost homogenous blacks without any noticeable screen bleeding (at least subjectively).

314
cd/m²
324
cd/m²
309
cd/m²
309
cd/m²
328
cd/m²
303
cd/m²
307
cd/m²
294
cd/m²
304
cd/m²
Distribution of brightness
Samsung 156HL01-102 tested with X-Rite i1Pro 2
Maximum: 328 cd/m² (Nits) Average: 310.2 cd/m²
Brightness Distribution: 90 %
Center on Battery: 328 cd/m²
Contrast: 863:1 (Black: 0.38 cd/m²)
ΔE Color 3.7 | 0.5-29.43 Ø5
ΔE Greyscale 4.85 | 0.57-98 Ø5.3
63% AdobeRGB 1998 (Argyll 1.6.3 3D)
69.4% AdobeRGB 1998 (Argyll 2.2.0 3D)
96.7% sRGB (Argyll 2.2.0 3D)
67.3% Display P3 (Argyll 2.2.0 3D)
Gamma: 2.35
Asus Pro B551LG-CN009G
GeForce 840M, 4650U, Kingston SVP200S37A256G
HP EliteBook 850 G1-H5G44ET
Radeon HD 8750M, 4600U, Intel SSD Pro 1500 Series SSDSC2BF180A4H
Lenovo ThinkPad S540 20B30059GE
Radeon HD 8670M, 4200U, WDC WD10JPVX-08JC3T5 + Sandisk SSD U110 16GB
Display
Display P3 Coverage
67.3
50.8
-25%
53.3
-21%
sRGB Coverage
96.7
72.3
-25%
76
-21%
AdobeRGB 1998 Coverage
69.4
51.9
-25%
54.6
-21%
Screen
Brightness middle
328
264
-20%
280
-15%
Brightness
310
264
-15%
274
-12%
Brightness Distribution
90
83
-8%
84
-7%
Black Level *
0.38
0.64
-68%
0.81
-113%
Contrast
863
413
-52%
346
-60%
Colorchecker dE 2000 *
3.7
11.37
-207%
10.84
-193%
Greyscale dE 2000 *
4.85
13.09
-170%
12.6
-160%
Gamma
2.35 94%
2.68 82%
2.76 80%
CCT
7077 92%
12953 50%
15823 41%
Color Space (Percent of AdobeRGB 1998)
63
47
-25%
48.7
-23%

* ... smaller is better

Even the black levels are quite decent, yielding 0.38 cd/m². Together with the high brightness, this leads to a more-than-decent contrast ratio of 863:1, more than twice as much as for the HP EliteBook 850 or the ThinkPad S540. In terms of color accuracy, the Asus device is the only one to stick close to what it should achieve, yielding good DeltaE values of 4 (ColorChecker) and 5 (grayscale), which even for an IPS panel marks a respectable achievement. Both competitors yield far higher values of 11-13, leading to a noticeable bluish tint (prior to calibration). Also, in terms of color space rendition, the more expensive IPS technology proves to be superior: 63% of the large Adobe RGB color space (only relevant for graphics professionals) is quite a feat, even for an IPS display, with the TN panels of its competitors only reaching 47 and 48%.

CalMAN Grayscale
CalMAN Grayscale
CalMAN ColorChecker
CalMAN ColorChecker
CalMAN Color saturation
CalMAN Color saturation


Asus Pro B551LG CN009G vs. AdobeRGB
Asus Pro B551LG CN009G vs. AdobeRGB
Asus Pro B551LG CN009G vs. sRGB
Asus Pro B551LG CN009G vs. sRGB
The laptop offers...
The laptop offers...
...a lot of flexibility outdoors.
...a lot of flexibility outdoors.

The matte, bright screen allows the laptop to be used outdoors with ease, even when bright areas such as the sky are reflected in the screen. In contrast to many other laptops out there, it is hard to find a position where the screen is actually not readable, rather than the other way around. Of course, direct reflection of sunlight is too much, even for the Asus laptop. Apart from that caveat, our test device is perfectly suited to being used outdoors.

Viewing-angle stability is yet another strength of the display of our test device. No inversions or misrepresented colors (as are common with TN panels), no matter whether horizontal or vertical deviations are examined, with just some minor brightness and contrast loss. This only changes once both horizontal and vertical angles are combined, but even then, the resulting issues are far less significant than with TN panels.


Even several people can use the device at once.
Even several people can use the device at once.

Performance

A fast ULV dual-core CPU - the Intel Core i7-4650U (2x 1.7-3.3 GHz, Hyper-Threading, TDP of 15 watts) based on Intel's most recent Haswell architecture - is used in the Asus laptop, capable (in theory!) of holding up to 2.9 GHz with both cores under load. Even demanding tasks such as image processing or HD video editing should pose no problems (the only exception might be massively parallel programs such as those used for 3D rendering, where more cores would lead to strong benefits). Having a look at the gaming performance, the CPU should rarely ever limit the mid-range GPU being used, an Nvidia GeForce 840M.

System information Asus Pro B551LG-CN009G

Processor

Like its preceding Ivy Bridge generation, Intel Haswell CPUs are made via a 22 nm process, coming with just slightly better performance levels yet much-reduced power consumption. For those programs which make use of Haswell's new command extensions, noticeable performance boosts are possible.

Our CPU tests via the Cinebench R11.5 (multi-core) benchmark lead to subpar results, no better than the nominally weaker Intel Core i5-4200U (2x 1.6-2.6 GHz, Hyper-Threading, TDP of 15 watts) used by the ThinkPad S540, even when utilizing both its cores. It should, however, be almost on par with the i7-4600U (2x 3.1-3.3 GHz, Hyper-Threading, TDP of 15 watts) used by the EliteBook 850-G1 which is 16% faster in these benchmarks. The explanation for this low multi-core result? The clock speed is the culprit, being reduced from 2.9 GHz to a maximum of 2.3 GHz (and sometimes even less). For comparison: The Intel Core i7-4600 used by HP manages to reach 2.6 GHz (and for prolonged periods of time), only throttling down to these levels after approx. 30 seconds. Our control device - also an Asus Pro B551 laptop, but with the i5-4200U CPU - actually reached the same multi-core results as the i7 variant, due to being able to hold the same 2.3 GHz. At least during the single-core test of Cinebench R11.5 is the i7-4650U capable of beating its i5-4200U-equipped colleague, but it still fares worse than other devices with a comparable CPU.

Thus, its performance is subpar compared to its capabilities and to the competition. While this may not always become apparent in real life, it can nevertheless be disappointing for those choosing the i7 variant due to its extra performance. One nice aspect: We didn't notice any differences while the device was running on battery.

CPU clock speeds Cinebench R11.5 Multi-CPU,...
CPU clock speeds Cinebench R11.5 Multi-CPU,...
...Prime 95 solo...
...Prime 95 solo...
...and Prime 95 + FurMark
...and Prime 95 + FurMark
Cinebench R11.5
CPU Multi 64Bit (sort by value)
Asus Pro B551LG-CN009G
GeForce 840M, 4650U, Kingston SVP200S37A256G
2.5 Points
Asus B551LA-CN018G
HD Graphics 4400, 4200U
2.48 Points -1%
Dell XPS 12 Haswell
HD Graphics 5000, 4650U, Liteonit LMT-256M6M
2.64 Points +6%
Apple MacBook Air 11 inch 2013-06 1.7 GHz 256 GB
HD Graphics 5000, 4650U, Apple SSD SD0256F
2.82 Points +13%
HP EliteBook 850 G1-H5G44ET
Radeon HD 8750M, 4600U, Intel SSD Pro 1500 Series SSDSC2BF180A4H
2.91 Points +16%
Lenovo ThinkPad S540 20B30059GE
Radeon HD 8670M, 4200U, WDC WD10JPVX-08JC3T5 + Sandisk SSD U110 16GB
2.5 Points 0%
CPU Single 64Bit (sort by value)
Asus Pro B551LG-CN009G
GeForce 840M, 4650U, Kingston SVP200S37A256G
1.36 Points
Asus B551LA-CN018G
HD Graphics 4400, 4200U
1.13 Points -17%
Dell XPS 12 Haswell
HD Graphics 5000, 4650U, Liteonit LMT-256M6M
1.45 Points +7%
Apple MacBook Air 11 inch 2013-06 1.7 GHz 256 GB
HD Graphics 5000, 4650U, Apple SSD SD0256F
1.42 Points +4%
HP EliteBook 850 G1-H5G44ET
Radeon HD 8750M, 4600U, Intel SSD Pro 1500 Series SSDSC2BF180A4H
1.43 Points +5%
Lenovo ThinkPad S540 20B30059GE
Radeon HD 8670M, 4200U, WDC WD10JPVX-08JC3T5 + Sandisk SSD U110 16GB
1.11 Points -18%
Cinebench R11.5 CPU Single 64Bit
1.36 Points
Cinebench R11.5 CPU Multi 64Bit
2.5 Points
Cinebench R11.5 OpenGL 64Bit
48.33 fps
Help

System Performance

System performance measurements not only include the CPU but also other aspects such as the RAM, the GPU and the mass storage device, which differ in their influence depending on the synthetic application scenario being tested during the PCMark 7 benchmark. While our test device is capable of beating the ThinkPad S540 by 20 to 30% in each and every category, the latter is the only device with just an HDD (plus a 16 GB SSD cache). The Asus laptop should in theory be on par with the HP, but it loses once more - not only due to its throttling issues, but also due to its rather sluggish SSD. Most recent laptops equipped with an i7-4600U beat the Asus Pro by 5 to 30% concerning the total PCMark 7 score - no matter the GPU. The PCMark 8 results are quite similar.

Our real-life impressions are better. Programs (as well as the system itself) start quickly, and even excessive multitasking doesn't bring the system to its knees.

Asus Pro B551LG-CN009G
GeForce 840M, 4650U, Kingston SVP200S37A256G
HP EliteBook 850 G1-H5G44ET
Radeon HD 8750M, 4600U, Intel SSD Pro 1500 Series SSDSC2BF180A4H
Lenovo ThinkPad S540 20B30059GE
Radeon HD 8670M, 4200U, WDC WD10JPVX-08JC3T5 + Sandisk SSD U110 16GB
PCMark 7
19%
-25%
Score
4176
5431
30%
3021
-28%
Lightweight
4585
5223
14%
3620
-21%
Productivity
3547
3929
11%
2852
-20%
Creativity
7115
8686
22%
5066
-29%
PCMark 8
Work Score Accelerated v2
3883
4908
26%
4106
6%
Total Average (Program / Settings)
23% / 21%
-10% / -18%
PCMark 7 Score
4176 points
PCMark 8 Home Score Accelerated v2
2654 points
PCMark 8 Creative Score Accelerated v2
3179 points
PCMark 8 Work Score Accelerated v2
3883 points
Help

Storage Devices

The main strength of most SSDs is their fast access times, especially for a large number of exceedingly small and disparate data blocks - a typical requirement at boot-up as well as during program starts. Recent SSDs should manage to achieve at least a 4k read speed of 20 MB/s - something the Kingston SSD used in the Asus Pro barely manages to achieve. Other benchmark results (with incompressible data blocks) yield the same overall impression: The Intel SSD used by the HP EliteBook is far faster, with sequential read rates being more than twice as high - this could e.g. become noticeable when starting games (which often require pre-loading large data files). The HDD used in Lenovo's ThinkPad plays in a different (meaning worse) league entirely, as can be seen by looking at the CrystalDiskMark 3.0 results. Those who are interested in more HDD and SSD benchmark results can find an overview here.

Asus Pro B551LG-CN009G
GeForce 840M, 4650U, Kingston SVP200S37A256G
HP EliteBook 850 G1-H5G44ET
Radeon HD 8750M, 4600U, Intel SSD Pro 1500 Series SSDSC2BF180A4H
Lenovo ThinkPad S540 20B30059GE
Radeon HD 8670M, 4200U, WDC WD10JPVX-08JC3T5 + Sandisk SSD U110 16GB
AS SSD
54%
Seq Read
214
454.6
112%
4K Read
19.15
23.84
24%
4K-64 Read
147
201.1
37%
Score Read
188
270
44%
CrystalDiskMark 3.0
41%
-84%
Read Seq
217.4
426.5
96%
99.3
-54%
Read 4k
24.71
27.84
13%
0.372
-98%
Read 4k QD32
145.2
164.7
13%
0.794
-99%
Total Average (Program / Settings)
48% / 48%
-84% / -84%
Kingston SVP200S37A256G
Sequential Read: 217.4 MB/s
Sequential Write: 149 MB/s
512K Read: 195.8 MB/s
512K Write: 189.4 MB/s
4K Read: 24.71 MB/s
4K Write: 108.3 MB/s
4K QD32 Read: 145.2 MB/s
4K QD32 Write: 157.2 MB/s

Graphics Card

The mid-range Nvidia GeForce 840M GPU with its 1 GB of dedicated RAM has already been presented to the public during March 2014, being one of the first Maxwell architecture models. It comes with both DirectX 11.0 and Nvidia's proprietary programming language CUDA, allowing (a tiny number of) optimized programs to let the GPU solve highly parallelized tasks. The 64-bit memory interface only allows for DDR3 memory to be connected instead of the much faster GDDR5 RAM. Still, this issue is not quite as severe due to the increased L2 cache being employed by the Maxwell chips.

At the time of writing, five other laptops with the same GPU can be found in our database. Looking at their benchmark results it becomes evident that - possibly due to a driver issue - only the integrated Intel HD 5000 GPU is being used during the Ice Storm benchmarks (low loads, DX9, graphics), yielding a much lower score than expected. The Cloud Gate (medium loads, DX10, graphics) benchmark results are more like it, beating its common mid-range predecessor, the GT 740M, by 20 to 30 % in most cases. Thus, most recent and graphically demanding games can be played smoothly with medium-to-high settings - still, this is no future-proof GPU. The AMD Radeon HD 8750 (GDDR5) comes close in terms of performance, especially under less demanding conditions. The Radeon HD 8670M, however, falls behind by approx. 50% during the pure graphics benchmarks. The physics tests show once more the suboptimal usage of the i7 CPU.

Asus Pro B551LG-CN009G
GeForce 840M, 4650U, Kingston SVP200S37A256G
HP EliteBook 850 G1-H5G44ET
Radeon HD 8750M, 4600U, Intel SSD Pro 1500 Series SSDSC2BF180A4H
Lenovo ThinkPad S540 20B30059GE
Radeon HD 8670M, 4200U, WDC WD10JPVX-08JC3T5 + Sandisk SSD U110 16GB
3DMark
-4%
-35%
1280x720 Cloud Gate Standard Graphics
9429
8882
-6%
4840
-49%
1280x720 Cloud Gate Standard Physics
2924
3127
7%
2450
-16%
1280x720 Cloud Gate Standard Score
6309
6303
0%
3977
-37%
1920x1080 Fire Strike Graphics
1605
1331
-17%
829
-48%
1920x1080 Fire Strike Physics
4121
4218
2%
3410
-17%
1920x1080 Fire Strike Score
1369
1241
-9%
767
-44%
3DMark Ice Storm Standard Score
35857 points
3DMark Cloud Gate Standard Score
6309 points
3DMark Fire Strike Score
1369 points
Help
low med. high ultra
Anno 2070 (2011) 120.3 62.5 39.3 19.5
Max Payne 3 (2012) 41.8 37.3 30.7
Medal of Honor: Warfighter (2012) 66 45 36 13
Call of Duty: Black Ops 2 (2012) 73.3 58.5 39.7 26
BioShock Infinite (2013) 89.1 51.4 41.8 14.4

Emissions

System Noise

The fan - although always on - can barely be heard among ambient noise while the laptop is idle. It gets a bit more audible under load (especially when both the CPU and the GPU are active), but there are no jumps in fan volume. Under maximum load, the fan noise becomes rather loud (its 42.7 dB(A) marks pretty much the average value of recent multimedia laptops), but - except for a slightly noticeable high-frequency pitch - not annoyingly so.

Noise Level

Idle
29.6 / 29.6 / 29.6 dB(A)
DVD
36.2 / dB(A)
Load
38.2 / 42.7 dB(A)
  red to green bar
 
 
30 dB
silent
40 dB(A)
audible
50 dB(A)
loud
 
min: dark, med: mid, max: light   Voltcraft sl-320 (15 cm distance)

Temperature

Our test device only gets really warm during continuous full load at the rear part of the bottom panel. Still, such stressful tasks will rarely occur during real-life usage on one's lap. Other parts of the device (such as the palm rest where it is more common to touch the laptop) don't even reach body temperature. While idle, no part of the surface does.

Once again, the stress test combining Prime 95 and Furmark shows that Asus is no master of thermal dissipation. The CPU clock speed (of both cores) decreases to 2.1 GHz and even further to 1.7 GHz for short periods of time. Both the CPU and GPU get hot (89 and 79 °C, respectively), but they remain within their specifications.

Max. Load
 36.8 °C
98 F
40.7 °C
105 F
30.7 °C
87 F
 
 31.6 °C
89 F
34.7 °C
94 F
26 °C
79 F
 
 27.3 °C
81 F
25.8 °C
78 F
26.3 °C
79 F
 
Maximum: 40.7 °C = 105 F
Average: 31.1 °C = 88 F
40.7 °C
105 F
46 °C
115 F
27.6 °C
82 F
41.1 °C
106 F
27.2 °C
81 F
26.3 °C
79 F
27.3 °C
81 F
26.3 °C
79 F
27.3 °C
81 F
Maximum: 46 °C = 115 F
Average: 32.2 °C = 90 F
Power Supply (max.)  42.6 °C = 109 F | Room Temperature 22.1 °C = 72 F | Voltcraft IR-360
(+) The average temperature for the upper side under maximal load is 31.1 °C / 88 F, compared to the average of 31.2 °C / 88 F for the devices in the class Multimedia.
(±) The maximum temperature on the upper side is 40.7 °C / 105 F, compared to the average of 36.9 °C / 98 F, ranging from 21.1 to 71 °C for the class Multimedia.
(-) The bottom heats up to a maximum of 46 °C / 115 F, compared to the average of 39.1 °C / 102 F
(+) In idle usage, the average temperature for the upper side is 28.2 °C / 83 F, compared to the device average of 31.2 °C / 88 F.
(+) The palmrests and touchpad are cooler than skin temperature with a maximum of 27.3 °C / 81.1 F and are therefore cool to the touch.
(±) The average temperature of the palmrest area of similar devices was 28.8 °C / 83.8 F (+1.5 °C / 2.7 F).

Speakers

The presets don't have much effect on how the speakers sound.
The presets don't have much effect on how the speakers sound.

We started by testing the speakers with the "music" preset (see image to the right) and some vocal-heavy titles such as this. Voices sound natural and powerful, albeit sometimes a bit harsh. Mids are over-emphasized, but this helps in making dialogue easier to understand in movies. Bass-heavy music is more of an issue, sounding thin and barely reproduced correctly. Not much in terms of dynamics or spatial effects could be noted. Although the speakers are located at the lower front of the device, aiming downwards, a reflecting surface doesn't help much in increasing the (in our eyes insufficiently low) maximum volume.

Energy Management

Power Consumption

When turned off, the Asus Pro B551LG-CN009G draws approximately 0.1 watts - this is completely unnecessary, as is the 0.4 watts during standby. 10.1 watts while idle, however, is slightly below average (for this kind of machine), and the results get even better when the laptop is put under full load. All 15.6-inch laptops which require less power run on far less powerful hardware. Then again, the throttling issues surely help with these results. The power adapter yields 65 watts - more than enough no matter what scenario we are in.

Power Consumption
Off / Standbydarklight 0.1 / 0.4 Watt
Idledarkmidlight 6.7 / 10.1 / 11.2 Watt
Load midlight 45.2 / 50.6 Watt
 color bar
Key: min: dark, med: mid, max: light        Voltcraft VC 940
Currently we use the Metrahit Energy, a professional single phase power quality and energy measurement digital multimeter, for our measurements. Find out more about it here. All of our test methods can be found here.

Battery Life

In terms of battery life, the Asus Pro can be compared to recent 15.6-inch multimedia laptops - yielding average runtimes both under load and during our real-life Wi-Fi test. Anyone who is interested in reading up on all the details of these tests can do this here. The Asus Pro could conceivably survive for longer stretches of time if the clock speeds while idle were not to remain at 2x 2.9 GHz - an issue which could only be solved by rebooting the system, while it occurred again once a single arbitrary program was opened and closed. This was quite a surprise as no processes producing significant CPU loads could be found by taking a closer look at the task manager.

Once more, our second test device (the one with an i5-4200 CPU) behaved normally, reducing its clock speed while idle. Still, the Wi-Fi battery runtime of both devices came to lie close together, with the i5 variant not even exceeding 5 hours instead of 4 hours and 39 minutes for the i7 model.

Battery Runtime
Idle (without WLAN, min brightness)
7h 59min
WiFi Surfing
4h 39min
DVD
3h 03min
Load (maximum brightness)
1h 41min

Verdict

The Asus Pro B551LG-CN009G
The Asus Pro B551LG-CN009G

Asus has promised quite a lot regarding the "professional quality" of the Asus Pro B551LG, but at least concerning our first test device, these promises backfired. Sharp edges, a malfunctioning USB port, insufficient CPU performance, issues with its Nvidia Optimus drivers during the Ice Storm benchmark, a rather slow SSD and a subpar numpad - that's quite a list. While our control device could rectify some of these points, other issues remained.

Still, the great display, the sturdy chassis, the more-than-decent haptics of the keyboard, the large number of ports and the usable speakers are definitely assets, as are the security features which should suffice for most mobile business professionals - at least those who don't mind the bulky case and the rather high weight. The system and GPU performances should be more than enough to play most recent games (including the demanding ones) with decent settings. This combination of features is indeed quite unique, separating the Asus Pro from the competition and making the relatively high price feel much more justified. Still, a sour taste remains due to our issues with the first test device.

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In Review: Asus Pro B551LG-CN009G. Test model provided by Asus Germany
In Review: Asus Pro B551LG-CN009G. Test model provided by Asus Germany

Specifications

Asus Pro B551LG-CN009G
Processor
Intel Core i7-4650U 2 x 1.7 - 3.3 GHz (Intel Core i7)
Graphics adapter
NVIDIA GeForce 840M - 1024 MB VRAM, Core: 1029 MHz, Memory: 2000 MHz, DDR3, 9.18.13.3235, Nvidia Optimus
Memory
8 GB 
, DDR3, 1600 MHz, single channel
Display
15.60 inch 16:9, 1920 x 1080 pixel, Samsung 156HL01-102, IPS, glossy: no
Mainboard
Intel Lynx Point-LP
Storage
Kingston SVP200S37A256G, 256 GB 
Soundcard
Intel Lynx Point-LP - High Definition Audio Controller
Connections
1 USB 2.0, 3 USB 3.0 / 3.1 Gen1, 1 VGA, 1 HDMI, 1 DisplayPort, 1 Kensington Lock, Audio Connections: Line In, Line Out (3.5 mm audio jacks), Card Reader: SD/SDHC/SDXC, 1 SmartCard, 1 Fingerprint Reader
Networking
Intel I218-LM (Clarkville ULT) Network Adapter (10/100/1000MBit/s), Intel Dual Band Wireless-N 7260 (a/b/g/n = Wi-Fi 4/), Bluetooth 4.0
Optical drive
HL-DT-ST DVDRAM GUA0N
Size
height x width x depth (in mm): 26 x 383 x 259 ( = 1.02 x 15.08 x 10.2 in)
Battery
45 Wh Lithium-Ion
Operating System
Microsoft Windows 7 Professional 64 Bit
Camera
Webcam: HD
Additional features
Speakers: stereo, Keyboard: Chiclet, Keyboard Light: no, Power connector, Recovery media, Warranty and information material, Asus Vibe Fun Center, ASUSPRO Business Center, WebStorage, Asus Live Update , 24 Months Warranty
Weight
2.5 kg ( = 88.19 oz / 5.51 pounds), Power Supply: 229 g ( = 8.08 oz / 0.5 pounds)
Price
1400 Euro

 

The velvet-like display lid is quite susceptible to fingerprints.
The velvet-like display lid is quite susceptible to fingerprints.
Depending on the ambient lighting conditions...
Depending on the ambient lighting conditions...
...the upper part of the base unit...
...the upper part of the base unit...
...appears to be either brownish or even purple.
...appears to be either brownish or even purple.
At the left-hand side...
At the left-hand side...
...most of the ports can be found.
...most of the ports can be found.
The maximum opening angle lies close to 180 degrees.
The maximum opening angle lies close to 180 degrees.
The actual letter keyboard...
The actual letter keyboard...
...sticks close to the standard layout.
...sticks close to the standard layout.
The keys come...
The keys come...
...with a great amount of travel...
...with a great amount of travel...
...and are just a joy to type on.
...and are just a joy to type on.
The same does not hold true for the numpad - it's simply too small.
The same does not hold true for the numpad - it's simply too small.
The conventional touchpad...
The conventional touchpad...
...didn't cause any issues during our test.
...didn't cause any issues during our test.
Business-like: The fingerprint reader.
Business-like: The fingerprint reader.
The on/off button.
The on/off button.
Stickers.
Stickers.
The SD-card slot is located right beneath the status LEDs.
The SD-card slot is located right beneath the status LEDs.
Webcam, microphones, ambient brightness sensor.
Webcam, microphones, ambient brightness sensor.
Optical drives are still very common in multimedia laptops.
Optical drives are still very common in multimedia laptops.
VGA and Ethernet (slides fully open) sound more business-like.
VGA and Ethernet (slides fully open) sound more business-like.
Maintenance hatch? Nope.
Maintenance hatch? Nope.
The latch belongs to...
The latch belongs to...
...the replaceable...
...the replaceable...
...and rather small battery.
...and rather small battery.

Similar Laptops

Devices from a different Manufacturer and/or with a different CPU

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GeForce 840M, Core i5 4210U
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GeForce 840M, Core i5 4210U
Acer Aspire E5-571G-536E Notebook Review
GeForce 840M, Core i5 4210U

Links

Price Check

Pros

+sturdy and stable
+great keyboard, decent touchpad
+bright display with a great contrast ratio
+beautiful, accurate colors
+great sharpness
+superb brightness homogeneity
+fast enough for most recent games
 

Cons

-rather heavy
-sharp edges (first test device)
-build quality not always on par
-numpad keys too small
-malfunctioning USB port
-some port locations not ideal
-CPU throttling issues
-extremely low Ice Storm score
-subpar battery life

Shortcut

What we like

The great variety of ports as well as security features, the nice keyboard and the powerful GPU make for a potent combination.

What we'd like to see

A decently-sized numpad.

What surprises us

That Asus chooses to send us such a disastrous test device; this is reflected in our verdict.

The competition

Lenovo ThinkPad Edge E540 20C6003AGE

Lenovo ThinkPad L540 20AV002YGE

HP ProBook 650 G1 H5G74E

HP ProBook 655 G1

Dell Latitude E5540

Dell Latitude 3540

Rating

Asus Pro B551LG-CN009G - 06/26/2014 v4(old)
Sven Kloevekorn

Chassis
73 / 98 → 74%
Keyboard
70%
Pointing Device
86%
Connectivity
62 / 81 → 77%
Weight
60 / 20-67 → 85%
Battery
82%
Display
86%
Games Performance
78 / 85 → 92%
Application Performance
75 / 92 → 82%
Temperature
86%
Noise
88 / 95 → 93%
Audio
70%
Add Points
-3%
Average
70%
78%
Multimedia - Weighted Average
Sven Kloevekorn, 2014-07- 1 (Update: 2018-05-15)