Dell Inspiron 15 7570 (i7-8550U, 940MX) Laptop Review

According to the manufacturer, the case is made of aluminum with "glass-bead brilliance." Whether there are glass beads or not, the silver aluminum case provides good stability and a high-quality appearance to the new Inspiron. The design is kept nicely modest, only the reflective "Dell" logo stands out in the center of the top.

The bottom with the keyboard base is comfortably sturdy, and there are no creaks when pressing down on it. The same goes for the lid, although naturally it is not quite as robust. Because of the aluminum, it appears more resistant than some of the plastic competitors. The lid cannot be opened with one hand, due to the relatively light base and the stability of the hinges, which hold the display in position well.

The openings for the speakers are at the bottom in the front, and the fan vents are further back. The battery is built-in, and there is no maintenance hatch.

The gaps between the top holding the keyboard and the bottom edge are not always completely even. In some places, the gaps turn out slightly larger. However, the workmanship in our test unit leaves a good impression overall.

The Inspiron offers all the usual connections. USB 2.0 is history, but unfortunately we are missing Thunderbolt 3. Instead, one of the USB-A ports offers support for PowerShare and the USB-C port supports DisplayPort. All the connections are on the sides of the notebook, most of them on the left. This is good for right-handed users, but not so good for left-handed ones. The distances between the ports are okay, but could have been even larger on the left side, since there is still plenty of space towards the front.

We are testing the transfer speeds of the card reader with our Toshiba Exceria Pro SDXC 64 GB UHS-II reference storage card. Unfortunately, the standard device does not strike such a good figure. In the JPG-file copy test, only the sibling model does worse, and in the sequential read test, the Lenovo also joins this slow group. For comparison, the Acer, which ranked highest in both SD tests, performed 150 to 230% better than the Inspiron! 

Things look much better in the test of the communication module. Our test unit achieved second place during sending as well as receiving. Only the Huawei and the Asus are similarly fast here.

Apart from a Kensington security lock, we did not see any other security features.

The manufacturer is stingy in terms of accessories, and apart from a quick-start manual and a warranty card, there is nothing else in the box of the Inspiron 15. However, Dell offers a range of external accessories, such as bags, docking stations, additional batteries, optical drives, and more. None of these accessories are exclusive to this model, so we are not including them in our testing. Dell's website offers further information.

The manufacturer offers a two-year warranty. Please see our Guarantees, Return Policies & Warranties FAQ for country-specific information.

Keyboard

Touchpad

The Intel Core i7-8550U is an energy-efficient processor of the Kaby-Lake-refresh generation. The power consumption is only 15 watts. Thanks to Hyperthreading, its four cores are able to run two threads each. They have a very variable clock speed of 1.8 to 4 GHz. The decisive factor is the cooling system and notebook configuration, determining whether the CPU can use its full performance potential or it is throttled because of high temperatures. 

In our 30-minute Cinebench loop, the typical behavior of the ultra-efficient CPU is showing. After the first, strong run, the values decline in the second run and then level off. For a short time, the CPU can get up to 44 watts, which means that the first run is not really representative. The outliers downwards trend without an external cause is striking. Perhaps there are some specific background processes that interfere with the performance, but we do not know the real reason.

The values that the sensors report via HWiNFO are also surprising. By just starting Cinebench, the core temperature jumps from 50 - 70 °C (~122 - ~158 °F) up to 98 °C (~208 °F) for a brief time, before they lower again to 71 °C (~160 °F). Such a sudden temperature change is not very likely, so we must question the information of the sensors on the core temperature.

In battery mode, the clock speed is 3.4 to 3.5 GHz on average. Away from the outlet, these values are decent. However, they also vary. If you run only the multi-core test, they barely average out at 2.4 GHz. In this way, the notebook achieves a value of about 526 points from the second run on. Compared to the 565 points when plugged in, this is only a slight throttling of about 7%.

A 512 GB Samsung PM961 SSD is used as the main storage. In our benchmark list, this model is one of the fastest SSDs ever, leading our list. Our measurements confirm the good performance of the NVMe disk; it is by far the best storage medium in the direct comparison with the competitors. So it is even more surprising that the Inspiron 15 was unable to gain more of an advantage in the system performance via PCMark. Perhaps the very variable clock speed of the CPU is responsible, since it can only rarely use its full potential (see Cinebench loop above).

As already mentioned, the 940MX is not suitable for serious gaming. While it offers slightly more performance than the integrated graphics unit, and both can be switched via Nvidia Optimus, the current games are not very enjoyable in minimum detail. You can see in the benchmark results that the graphic performance is quite reduced, since the competing models with the same card achieve higher frame rates.

For example, even in the lowest resolution and the lowest details, it cannot really display "The Witcher 3" smoothly. The Inspiron 15 7570 achieves 26 FPS on average in these settings. Anything more than that is not playable anyway. Normally notebooks with the 940MX reach about 35 FPS here, so the performance is throttled.

At least you can play "Rise of the Tomb Raider" smoothly in the minimum settings, but is there anyone who wants to do this? Even in medium settings, Lara moves only at a snail's pace.

Even at its lowest settings, "Doom" became a benchmark torture for the tester. About 14 FPS in the minimum configuration is not comfortable to test, but the device is not really a gaming but rather a business model. Normally "Doom" is less demanding than "The Witcher 3." Since notebooks with the 940MX normally achieve about 39 FPS and "Doom" is our last game of the test series, we definitely saw additional throttling over time here.

The general throttling of the graphics performance and the additional throttling over time have a negative effect on the comparison with the competitors. Most of the time, the Inspiron 15 can be found in one of the last places, and the Huawei and the Asus mostly fare much better. But the results in the other models are also quite variable, depending on the resolution and details.

Finally, we have to negate the gaming suitability of the Inspiron 15 7570. While it might still be enough for a game of "Rocket League" or one of the older "FIFA" games in much reduced settings, the device does not have sufficient power for the current, demanding games. But this is Dell's fault, since the graphics card should at least do a little better and enable playing games in the lowest settings. However, the performance is throttled considerably at times.

As with so many notebooks, the audio reproduction cannot convince in this notebook either. The maximum volume is not particularly high, and the bass reproduction is worse than mediocre. The sound spectrum is thin and not enjoyable. 

You can connect external audio devices such as headphones, a stereo system, or microphone via the combined headphone/microphone port.

Frequency comparison (Checkboxes selectable!)

While idling, the Inspiron is efficient. Thanks to Optimus and the very variable processor speed, it keeps up with the competition. Under load, the picture changes slightly. Despite the relatively strong performance throttling, our test unit consumes more power than most of the competitors during very demanding work. Only the Acer and the sibling model consume a similar amount during maximum load. We measured a top value of 59 watts. The included power supply is rated at 65 watts, which should be sufficient.

The Inspiron 15 has a 42-Wh battery. To establish how long the device can last away from the mains outlet, we test various scenarios.

For the maximum runtime, we deactivate all the communication modules, minimize the brightness, and activate power saving mode. We simulate a minimal load via the BatteryEater read benchmark. In this way, our test unit lasts for a maximum of 4 hours and 40 minutes. For an all-rounder with such built-in hardware, this is anything but a top value. In the comparison, this is only sufficient for the last place. The next best competitors last almost twice as long. However, since the Acer and Lenovo lack some important measurement data, they are dropping out of the comparison.

To measure the minimum runtime, we turn up all the power users and simulate a large load with the BatteryEater Classic test. The Inspiron lasts for only 1 hour and 20 minutes. Even though all the competitors come out close together here, this measurement is anything but satisfactory.

We activate the Balanced mode in the WLAN practice test, reduce the brightness to 150 cd/m², and surf the web with changing pages via a script. The test unit achieves a runtime of 1 hour and 45 minutes, which is quite subterranean for a notebook of this price range.

In our video test, the Inspiron achieves about 4 hours. The power saver mode was active, the communication modules deactivated, but the brightness was maximized.

Overall, the battery life of the Inspiron 15 is a negative surprise. Although the device is relatively light and offers Optimus and an energy efficient processor, the measured runtimes are very weak, which clearly limits the mobility that it has aimed for. Considering the hardware, it is a mystery to us as to why the device does so badly here.