Dell XPS 12 9250 4K Convertible Review

Keyboard

The included keyboard dock for the XPS 12 9250 is a chiclet keyboard with a subtle white backlight. The keys have a size of 14 x 14 millimeters spaced at 3 millimeters. The key drop is 1.9 millimeters and offers a clear pressure point. The key stroke provides the user with a good feedback. The matte, lightly roughened keys are all at the same height. The keys are big enough so that nothing stands in the way of energetic typing. The keyboard layout offers a good overview and does not look too cramped. The subtle, white backlight also enables working in poorly illuminated work environments. The brightness can be set in two levels. It can also be turned off completely so that the battery runtime is not unnecessarily shortened. The stability is quite good thanks to the rigid keyboard dock. A lot of pressure has to be applied to dent areas on the keyboard.

The touch-sensitive pad without dedicated keys is almost centered below the keyboard. With a surface area of 100 x 55 millimeters, the space on the keyboard dock has been utilized ideally. The surface is sleek and provides good gliding properties up to the edges. The cursor can be moved accurately and quickly over the desktop. The keys in the lower part of the touchpad provide the user with good feedback. A quiet, short click is audible when the keys are used. The keys' pressure point is also sufficient and an unintentional click will be rather rare.

The touchscreen has a diagonal of 31.8 centimeters and has a resolution of 3840x2160 pixels. We did not have any problems with the touchscreen in the test period. The 4K multi-touchscreen is very responsive; all inputs were implemented instantaneously. The screen's surface is agreeably smooth and allows accurate inputs. It could tilt back a bit when used in the keyboard dock, but that is not distracting. A possible disadvantage might be the narrow left and right edges. The touch surface could be unintentionally brushed when used without the dock held in a hand.

Dell touts its XPS 12 as having the best 4K panel of its class. But first things first: A native resolution of 3840x2160 on a diagonal of 12.5-inches leads to a pixel density of 352 PPI. The screen's average brightness of 399 cd/m² is very impressive and even allows working in a bright environment. The illumination of 81% could be somewhat better. A decent contrast ratio also ensures a rich reproduction on the 4K panel. However, we see some unsightly backlight bleeding on a completely black screen. This will not restrict routine use, though. PWM flickering could be measured at a screen brightness of 20%. That should not cause problems even for sensitive users due to the high frequency of 1000 Hz.

Dell's XPS 12 9520 is a 12.5-inch convertible laptop. The convertible offers enough computing power for office routine. Dell's device easily copes with Internet browsing or rendering media content. Our review sample, the premium model based on Intel's Core m7-6y75 processor and 8 GB of LPDDR3 RAM, has more than enough performance reserves to process several applications simultaneously. The generous 512 GB PCIe SSD also provides plenty of storage and contributes to smooth workflow. Dell lists the review sample at a purchase price of 1799 Euros (~$2051). The entry-level version is available for 1249 Euros (~$1423). Higher-performance devices with faster Core i processors, such as Microsoft's Surface Pro 4, exist in this price range but they cannot offer noiseless operation.

The review sample makes an overall positive impression. However, buyers who opt for a Core m7 processor in this performance range should not expect a speed marvel. Nevertheless, fast and smooth workflow in conjunction with noiseless operation reaps in plus points here.

As to the processor, Dell relies on Intel's Core m lineup. The processor is based on the Skylake architecture. Our review sample houses the top model of this lineup, Intel's Core m7-6Y75. The manufacturer can limit the Turbo Boost bandwidth owing to the configurable TDP. Dell crops the maximum Turbo rate here. Theoretically, 2.9 GHz would be possible when both cores are utilized. A maximum clock of 2.6 GHz is recorded in the single-core test of the Cinebench R15 benchmark. It cannot be maintained permanently, though. The CPU Multi 64-bit test is performed at a CPU clock of 1.8 - 1.9 GHz. Microsoft's Surface Pro 4 with Intel's Core m3-6Y30 can place itself before Dell's XPS 12 9250 here. A much better performance development is seen in the CPU Single 64-bit test. Asus' Zenbook UX305CA-FB055T furnished with the same SoC as our review sample manages to retrieve approximately 9% more performance from the small chip when all cores are utilized. The processor would be capable of even more, but the manufacturer limits the performance development due to the fanless and compact design in favor of stable operation even during full load. Presently, no convertible on the market can implement the full performance of Intel's Core m7.

The review sample performed our stress test (Prime95 and Furmark run for at least one hour) in the same manner in both AC and battery modes. At the beginning of the test, the processor clocked at 1.4-1.8 GHz which is reduced gradually until it settles to 900-1000 MHz. We measured a maximum temperature of approximately 44 °C on some spots of the casing. However, these rates do not represent a normal condition and should not be reached in routine use. 30 °C is only surpassed on three points in idle.

Dell's XPS 12 9250 is a slim, 12.5-inch convertible. The installed Intel Core m7 6Y75 processor has enough power for routine tasks, and its TDP allows passive cooling. The SSD impresses with high read rates and ensures a fast-running system. The high-resolution, 12.5-inch screen with 3840x2160 pixels convinces with high contrast, good color-space coverage and strong viewing-angle stability. It is also very responsive as an input device and implements commands instantaneously. The keyboard dock nicely matches the tablet's looks and pleases the user with a quiet keyboard and accurately functioning touchpad.

At first glance, an elegant convertible that becomes even more interesting when looking closer at the specifications. The question remains whether Dell has perhaps set the price too high, though.

Despite all that, there is still reason for criticism. The tilting angle cannot be adapted to the seating position, which does not allow an ergonomic work position at the desk. Although the review sample is furnished with the strongest processor from Intel's Core m lineup, the performance cannot be completely retrieved. Thus, Microsoft's Surface Pro 4 with a Core m3, for example, is sometimes much faster. We would also have hoped for a longer battery life. The battery performance should be somewhat better in a tablet that is also marketed for the business sector.

Purchase recommendation or not - anyone thinking about buying this kind of device will now know what shortcomings have to be expected and/or what convincing aspects the device has. Dell demands an exorbitant 1799 Euros (~$2051) for the test configuration. That is definitely not a bargain, but it is one of the few devices with a 4K panel in a 12.5-inch size - if that is the driving force. Perhaps a configuration with a weaker CPU would come into question since the full performance of the installed Core m7 processor cannot be retrieved anyway.