Dell XPS 15 Notebook Review

The hardware at work in the Dell XPS 15 reacts to commands very quickly. One of the device's highlights is a high-end Intel Core i7-4712HQ quad-core processor. Dell chose to stick with the predecessor's 16 GB of dual-channel DDR3 memory. As in the 2013 model, an Nvidia GeForce GT 750M takes care of graphics performance. Unfortunately, Dell has yet to indicate a future option to upgrade to a GPU from the newer Nvidia GeForce 800 or soon-to-be-released 900 lines. In its current configuration, the test device is a high-midrange model predestined for use in the multimedia arena, especially for image, graphics and video editing.

The Dell XPS 15 is equipped with a powerful quad-core processor from Intel. In our current model, the chip runs 100 MHz faster than its predecessor's. That means the Intel Core i7-4712HQ has a base clock rate of 2.3 GHz. In turbo mode, the clock frequency can rise to up to 3.3 GHz. Unlike other HQ models from the i7 line, the "2" in this processor's name indicates a low TDP. In our case, according to the manufacturer, the chip generates up to 37 W of heat - 10 W less than other HQ processors. The Cinebench R11.5 benchmark should reveal the efficacy of the 100 MHz increase in clock frequency. The difference between the CPU at work in our test device and the chip in the 2013 model proves to be almost imperceptible - the new notebook only scored 2% higher than the older model in the multi-core test. The CPU ran at a constant 3 GHz during the Cinebench test, which means that the computer is unable to take full advantage of the processor's turbo mode under load. In battery mode, the CPU frequency slowly rose from 800 MHz to 2.9 GHz, which explains the loss of about 40 points in the end result of the Cinebench R15 benchmark. Without a power outlet nearby, the computer will have less CPU performance at its command. 

Short reaction times make working more of a breeze. Thanks to the fast storage medium and dual-channel RAM, our interaction with the system was always quick and smooth. The accuracy of our subjective impression was confirmed by PCMark 7, although the results are a bit perplexing at first glance. The hardware Dell chose to install in our test device is slightly more powerful than the components at work in the predecessor model, but the new notebook's results are considerably worse than the previous machine's. This could be a first clue that the change of SSD manufacturer wasn't necessarily a positive one.

Compared to the storage device at work in the predecessor model, Dell "only" switched manufacturers - the amount and type of storage remain the same. Instead of a storage medium from Samsung, our XPS is equipped with a solution from LiteOn-IT. The AS SSD benchmark's analysis reveals that the new SSD's sequential read and write rates are somewhat slower, but its results in the more important 4k tests are stronger. Of the drive's 512 GB, the Windows partition has 457 GB at its command. A further 20 GB belongs to the recovery partition.

The Dell XPS 15 is still outfitted with the Nvidia GeForce GT 750M, first introduced at the beginning of 2013. Due to the fact that the current configuration's more powerful CPU has very little effect on the notebook's graphics performance, more information regarding the GPU's performance reserves can be gleaned from our review of the Dell XPS 15 (Late 2013). Out of the benchmark tests we performed, only 3DMark Cloud Gate showed an inexplicable, substantial improvement of 22%. For further comparisons and benchmarks, see our benchmark list of notebook graphics cards.

Unfortunately for gamers, even somewhat older games can only be enjoyed at low or medium graphics settings. Additionally, the notebook is only able to reach fluid frame rates if the display resolution is dramatically reduced. In the game BioShock Infinite (2013), we see that the stronger CPU doesn't have a significant effect on performance. For current games, the GT 750M GPU at work in our test device plainly proves to be too weak. Even though the XPS 15 clearly isn't primarily designed for gaming, we would expect a premium notebook - which Dell obviously intends for the XPS 15 to be - to have up-to-date hardware for maximum graphics performance.

The XPS 15's fans perform their task discreetly until the system is under stress. In idle mode, we only heard subtle sounds of up to 32 dB(A). Not even under load does the system generate a disruptive level of noise. The fans run at a distinctly audible 45 dB(A) and whir more loudly than in our test device's predecessor, but the dull sound of the fans isn't bothersome. We did notice in our tests, however, that the fans occasionally grew noticeably louder for no apparent reason. It's not clear whether some specific piece of software in our test device is at fault for this.

The combination of the notebook's thin build and powerful hardware components has an unmistakable effect on the device's case temperatures. Advantageously, however, the rubberized surface of the keyboard proves to be heat resistant.

Even with its brightness level set to minimum and its communications modules deactivated, at a power consumption rate of 14.6 W, our test device is rather thirsty. The notebook's predecessor was more frugal, only using 10-17.4 W in idle mode. The increase in power usage may be traceable to the 4K display.

The difference between the results in our medium and maximum load tests is especially striking. Under medium load, the XPS requires between 90 W and 96 W. When we start our stress test using Prime95 and Furmark, however, the machine only needs about 86 W. This can be traced to the aforementioned CPU throttling.

Dell once again chose to equip their XPS 15 with a relatively large 91 Wh battery with 6-cells. The notebook's energy consumption rates lead one to surmise that our current test device will run out of steam faster than its predecessor. We are, however, unable to make a perfect comparison, as our WLAN test has been revised since the 2013 review. After a little over 5 hours, the new XPS needs to be plugged back into the wall. Unfortunately, though the XPS is designed as a work and multimedia device, it won't last through a full workday without a connection to a power outlet. The predecessor kept chugging along for almost 9 hours in our test, though the test parameters were slightly different.