Review HP Split x2 Convertible

At a combined weight and thickness of 2.3 kg (1.0 kg tablet + 1.3 kg base) and 22.9 mm (11.3 mm tablet + 11.6 mm base), respectively, the Split x2 is on the heavy side when compared to standard 13.3-inch netbooks or convertibles. The Yoga 13, Vaio Duo 13, LifeBook T902, Transformer Book TX300 and Taichi 31 – all of which are 13.3-inches in screen size – are either much thinner or lighter or even both. The weight difference can be partly attributed to the secondary battery of the Split x2 for potentially longer battery lives than the competition, but there is no denying that the HP convertible is certainly weighty for the size.

Consequently, the heavy build has resulted in good construction quality all-around. We were a bit worried that case quality may have taken a hit due to the “cheapening” on the original Envy x2 design, but we’re pleased to say that both the tablet and base portions exhibit better-than-average resistance to finger depressions and twisting. Rigidity is not as good as the Envy x2, for example the backside of the tablet can still be depressed down the center. The base does show a bit more flexing than the tablet around its edges, keyboard center and palm rests, but it’s certainly not a cause for concern.

Unfortunately, the two connecting hinges that attach the tablet to the base allow for far too much wobbling. When the display is set at a comfortable angle, the hinges are simply not stiff enough to secure the screen from tilting back and forth. This isn’t so much of a problem when using the convertible on a flat desk, but we certainly would not trust transporting the device without closing the lid first. Like other tablet convertibles such as the Lenovo IdeaTab S2110, the top-heavy tablet portion can be a bit too much for the hinges if not careful. Though adequate, the locking mechanism here leaves room for improvement.

Visually, the Split x2 is similar to the Envy x2 in terms of color and smooth textures with a couple of major differences. Firstly, the keyboard surface is now black and a fingerprint magnet with a more obvious inexpensive plastic compared to the higher-quality lid and base. Secondly, the brushed aluminum surface of the Envy x2 is now matte silver plastic that can scratch quite easily. Combined with the thicker chassis, the Split x2 doesn’t look nearly as luxurious as its smaller-but-older brother, though we have to commend HP’s successful efforts in maintaining much of the rigidity and structural construction of the original.

Keyboard

The matte plastic chiclet keyboard (28.5 cm x 10 cm) on the dock shows no issues in terms of responsiveness while typing. Note that travel is very shallow and feedback feels very light (similar to the Envy x2 keys), so it may take some time to become fully accustomed to the “featherweight” feel of the keys. The narrower top row of function keys feel notably mushier than the QWERTY set and the split Up and Down directional keys can be difficult to use precisely for larger fingers. The lack of a keyboard backlight is to be expected as the more costly Envy x2 skipped this feature as well.

Touchpad

The Synaptics matte touchpad is capable of recognizing up to 4-finger inputs for Windows 8 Edge Swipes, rotation, scrolling and flicking. It may not be very large (9.5 cm x 6 cm), but its size suitably fits the chassis and is responsive to basic point and clicks as well as multi-touch commands with minimal misreads. Zooming still feels a bit slow and delayed compared to Android devices, though that may be more software-related than hardware. If an external mouse is detected, the touchpad will automatically disable.

Since the display is a touchscreen, many of these same commands can simply be performed directly on the screen itself. In this case, we ran into no issues with inaccurate input recognition or delays between scrolling, swiping or snapping windows in and out of focus.

Color space reproduction covers about 64 percent of the sRGB standard and subsequently even less of the AdobeRGB spectrum, which is common amongst budget displays. The majority of consumer-oriented notebooks exhibit similar coverage such as the Dell XPS 12 and Lenovo Twist below, but this should not be a concern for the average household user where color reproduction is normally not a huge factor.

Further display measurements were performed with an X-Rite i1Basic Pro 2 spectrophotometer. Color accuracy before calibration is middling with a deltaE average of over 8 units. Fortunately, the deviation becomes much smaller the more saturated the colors become, though Blue, Cyan and Magenta show little improvement. Colors and even grayscale after calibration become much more normalized across the board, especially Cyan and the correlated color temperature.

CPU performance is most similar to the previous generation Sandy Bridge ULV Core i3-2377M. As examples, the single-threaded Super Pi 32M benchmark completes in 1401 seconds vs. 1338 seconds in the i3-2377M and the multi-threaded wPrime 1024M benchmark completes in 1220 seconds vs. 1141 seconds in the Sandy Bridge equivalent. CineBench scores are also slightly better for the older model compared to the i3-3229Y. Instead, the improvements that the newer IVB model brings are not related to raw performance, but performance-per-Watt. The i3-3229Y is still very close in performance while consuming less power (13 W TDP vs. 17 W TDP) and operating at a lower clock rate (1.4 GHz vs. 1.5 GHz) than the i3-2377M. The ULV Core i3 here is a great balance for those wanting more power than both Atom CPUs and ARM-based SoCs without losing too much battery life from much more powerful standard voltage mobile Core i3 or i5 solutions.

PC gaming on a tablet is not exactly mainstream just yet and users shouldn't be surprised at the subpar graphics performance of the Split x2. Compared to the average HD 4000 GPU in our database, the GPU in the Split x2 is below average due to its ULV CPU and reduced GPU Turbo Boost potential. As an example, Guild Wars 2 and Starcraft 2 run at 22 FPS and 70 FPS at their lowest settings, respectively, while the average HD 4000 across all benchmarked notebooks can run these same games at 36 FPS and 111 FPS under the same settings. Beyond casual gaming at very low settings or Flash games, the Split x2 is not capable of playing many of today's popular PC titles.

The final 3DMark 11 score of 425 points places the Split x2 right next to other notebooks sporting the same GPU paired with similar ULV IVB processors. This includes the Acer Aspire S3-391 (421 points) and Fujitsu Lifebook U772 (425 points) with a Core i5-3317U and Core i6-3427U CPU, respectively. Compared to, say, a ThinkPad Edge E431 with the same GPU on a standard voltage CPU, the Split x2 is slower by nearly 150 points in the same benchmark.

We stress the CPU and GPU in our convertible while having CPU-Z, GPU-Z and HWiNFO monitoring tools running to identify any potentially throttling or stability issues. With only Prime95 active, the CPU was seen operating at its maximum 1.4 GHz as advertised. Occasionally, the core will dip to 1.2 GHz, but will quickly jump back to its rated 1.4 GHz rate. With only FurMark active, the GPU was running at 850/800 MHz (core/memory) and very quickly dropped and stabilized to 500 – 550 MHz core after just a few seconds. Though the HD 4000 may be rated at 350 MHz with Turbo Boost up to 850 MHz, it is not uncommon for ULV processors to have the integrated GPU run at lower Turbo Boost frequencies due to a lower TDP overhead.

When under maximum stress with both Prime95 and FurMark active simultaneously, both the CPU and GPU were observed to be running smoothly at 800 MHz and 350 MHz, respectively, and never any higher. Fortunately, both cores never fell below these base frequencies either, suggesting no major throttling issues despite its tablet form factor. We note that the GPU load was seen fluctuating between 83 percent and 100 percent according to GPU-Z, which also suggests a power bottleneck preventing full utilization of then GPU when the CPU is under stress. At the end of the stress test, the CPU core was a recorded 70 degrees C and a 3DMark 11 run immediately following the test returned no statistically significant changes in final scores (425 before stress vs. 421 post stress).

System performance is not reduced when running on battery power. Both the CPU and GPU are able to maintain their respective clock rates and a 3DMark 11 run on batteries again returned no statistically significant changes in final scores (425 before stress vs. 424 on batteries).

Unlike say the IdeaTab S2110, the Split x2 utilizes a primary 3-cell 33 Wh Li-polymer battery as well as a secondary 3-cell 32 Wh Li-polymer located in the dock itself. Though accessible by removing their respective back panels, the modules are not meant to be removed or replaced in a convenient manner. The primary battery is larger than the 26 Wh equivalent in the Envy x2 and its combined 65 Wh of power is more than the Taichi 31 (53 Wh), Yoga 13 (54.7 Wh) and Vaio Duo 13 (47.4 Wh), but smaller than the Lifebook T902 (72 Wh).

Our battery life tests were performed with the dock connected and since the battery module in the dock is roughly the same as the module in the tablet in terms of capacity, halving our results below will give a good idea of how long the tablet can last just off of the primary.

When under ideal battery runtime conditions (Power Saver mode, minimum brightness with no timeout, and inactive wireless), the Split x2 was able to last for almost 11 hours. Our more realistic WLAN condition puts the convertible in Balanced mode at a brightness as close as possible to 150 nits – in this case, the maximum brightness setting – while looping our standard script to simulate typical browsing conditions. The unit was able to last for 6 hours before automatic shutdown.

The large discrepancy between the idling and WLAN runtimes show that users should be able to squeeze at least an hour or so more from the batteries with low usage and more reserved battery-saving system settings. Our measured 6 hours during constant WLAN use is certainly longer than the 4-5 hour Taichi 31, LifeBook T902 and IdeaPad Yoga 13, but comes a bit short compared to the Vaio Duo 13 and especially the IdeaTab S2110 and Envy x2. The latter two can be explained by their extremely low-power Snapdragon and Atom processors compared to the i3-3229Y in the Split x2.