Lenovo ThinkPad Yoga 14 Convertible Review

Right away the ThinkPad Yoga 14 leaves a very good impression. The chassis is Mil-Spec tested and nearly identical to the 12-inch ThinkPad Yoga including the strong magnesium alloy body and placement of ports with slightly modified dual-hinges to accommodate the larger and heavier display. The matte dark gray surfaces all-around are akin to a ThinkPad, but the looks and feel of the Yoga 14 are closer to the Yoga series as the model lacks the slightly textured sharp and boxy aspects of a dedicated ThinkPad. The edge-to-edge glossy glass display, for example, is a dead giveaway that this is no traditional ThinkPad. Nonetheless, the Yoga 14 shows better resistance to twists and depressions on all corners and surfaces than a dedicated Yoga. A couple of areas could be better, however, including the centers of the keyboard and outer lid where the surfaces can still warp from moderate pressure. This certainly makes us miss the roll cage that is now becoming less prevalent on recent ThinkPads.

At 20.3 mm thick, the Yoga 14 is just slightly thinner than the more traditional ThinkPad T440 (21 mm), yet still thicker than the 14-inch Sony Vaio Flip 14A convertible by half a millimeter. Its weight of about 1.9 kg is also very similar to the Sony and quite heavy for the size as it is surprisingly heavier than the ThinkPad T440 (1.7 kg) and, of course, 14-inch Ultrabooks like the HP Folio 1040 (1.5 kg) and Toshiba Tecra Z40T (1.6 kg). This makes the Yoga 14 less fit for on-the-go tablet use and Lenovo seems to even discourage it as the manufacturer does not include a stylus with the Yoga 14 in contrast to the built-in stylus found on last year's 12-inch model.

The added weight does make the notebook feel well-made with no unintended creaks or crevices between materials when switching between its multiple modes. Flipping the display is quick and easy with strong hinges on all angles. We appreciate the attention to detail from Lenovo as evident by the automatic Lift n' Lock keys and the rubber footing on the front edge of the unit for better stability in Tent mode. Other convertibles with similar 360 degree hinges like the Toshiba Radius P50W do not have either of these features.

Keyboard

The chiclet keyboard (29 x 11.5 cm) is the standard AccuType fare that was introduced on the X1 Carbon and is now prevalent on newer ThinkPad models. Travel is only adequate as is common on Ultrabooks, but the plastic keys have good tactile feedback without being "mushy" or soft. The same cannot be said for the the PgUp, PgDn, and directional keys, unfortunately, as they are smaller in size, softer in feedback, and generally more difficult to use for larger fingers. Grease and fingerprints accumulate quite easily on the flat keys as well. The beveled keys of old still have the superior travel and feedback, but we can appreciate the continued improvements on the AccuType feel and style. The keys here certainly perform a bit more solidly than on Samsung's ultrathin Book 9 models and are also spill-resistant.

Like its smaller 12-inch sibling, the Yoga 14 offers a one-level keyboard backlight with Lift n' Lock to automatically depress and disable all keys when the display is pulled back past the 270 degree mark. Note that while the touchpad is automatically disabled in this state as well, it will not depress like the keyboard keys do. The keyboard can also be lifted and removed if needed, but the Lift n' Lock mechanism makes the keyboard more fragile during disassembly compared to older ThinkPads. 

Touchpad

The smooth glass touchpad is large (10 x 7.5 cm) and is essentially the same as the touchpad found on the 14-inch ThinkPad T440 and ThinkPad T440s. Thus, we find feedback and responsiveness to be above average with no cursor jumping or other bugs. Multitouch gestures in particular are especially easier to perform due to the larger surface area and the integrated mouse clicks are recognized reliably for the most part. It is indeed possible to click the touchpad without it registering onscreen, but only by clicking slowly on the bottom corners of the surface.

Accompanying the touchpad is the standard ThinkPad trackpoint. While the trackpoint itself works reliably, using the trackpoint in combination with the new touchpad is a little trickier compared to the touchpads on older ThinkPads. It's a trade-off that core ThinkPad users will need to become accustomed to.

Of course, the 10-point capacitive touchscreen will accept inputs as well. In this case, the screen responds swiftly and reliably without any notable bugs or issues. Fingerprints will accumulate quickly like on any other convertible touchscreen.

Color space reproduction is good at 79 percent and 58 percent of the sRGB and AdobeRGB spectrums, respectively. This is nearly identical to the ThinkPad T440s, but is only about 80 percent of the gamut of the Sony Flip 14A. Nonetheless, colors are much deeper than a standard budget TN panel where sRGB coverage is typically only around 60 percent.

Further display measurements with an X-Rite spectrophotometer reveal good color reproduction and grayscale out-of-the-box. In fact, color accuracy is quite consistent across all saturation levels which is not common amongst uncalibrated displays. Outside of professional digital artists, extreme color precision is not a high priority for the Yoga 14.

Outdoor usability is possible but not recommended under sunny or otherwise bright conditions. The backlight is not sufficiently bright enough to overcome the inevitable glare from the glossy display. The hinges do allow for more leeway to avoid the glare, but maximum display brightness under shade is recommended nonetheless. In this case, a brighter tablet or Ultrabook like the Surface Pro 3 or Dell XPS 13 is preferable for more comfortable extended outdoor use.

Processor

The i5-4210U is a common ULV Haswell CPU that can also be found on other popular notebooks like the IdeaPad Flex 2 15 and Envy 15 x360 convertible. Performance from the Yoga 14 CPU is in the same ballpark compared to these other devices. Its wPrime 1024m score of 657 seconds, for example, is similar to the IdeaPad Z50, while its single-core Super Pi 32m score of 730 seconds is similar to the Aspire V5-573G. These scores are only slightly better than the i5-4200U, which is just 100 MHz slower in clock rate. When compared to the previous Ivy Bridge generation, the i5-4210U is most similar in performance to the i5-3427U while operating at a lower TDP (15 W vs. 17 W) and slightly lower clock rate.

More information and benchmarks on the i5-4210U can be seen in our dedicated CPU page here.

System Performance

PCMark 7 places the ThinkPad Yoga 14 alongside other notebooks with dedicated GPUs like the Dell Inspiron 17R and HP Envy 15. Nonetheless, system performance feels a little on the slow side due to the 5400 RPM HDD. The PCMark 7 raw system storage score of only 683 points is much below the 12-inch ThinkPad Yoga and its 4686 points in the same benchmark. As such, the older and less powerful 12-inch ThinkPad Yoga scores around 1500 points higher in PCMark 7 overall.

Subjectively, the system runs noticeably slower than a system with a dedicated SSD. Software installations definitely take longer and the HDD is almost certainly bottlenecking the system. The 16 GB SSD cache does little in speeding up new applications. However, it does work as intended for commonly used applications as a second PCMark 7 run immediately following the first raised the final score from 3226 points to 3738 points with nearly double the raw system storage score.

Gaming Performance

The mid-range GeForce GT 840M is based on Nvidia's latest Maxwell architecture complete with 384 shaders, 24 TMUs, and 8 ROPs. Performance is roughly on par with the older 750M and 650M GPUs according to 3DMark 11 while consuming less power by an estimated 10 Watts. This allows the 840M to be in smaller notebooks compared to the 750M or 650M and still offer comparable performance.

While great for 720p gaming, playing games in Full HD will quickly tax the 840M and its narrow DDR3 VRAM bandwidth. The GPU simply cannot run advanced graphics features at 1080p with respectable frame rates. Playing modern 3D games at 1080p will demand the user to reduce all other graphical settings to near minimum. More casual titles like FIFA or Sims will run more comfortably at the native screen resolution with less frame rate issues.

More technical information and benchmarks on the GT 840M can be found on our dedicated GPU page here.

We stress test the Yoga 14 with HWiNFO, CPU-Z, and GPU-Z monitoring tools to identify any throttling or stability issues. With just Prime95 active, the CPU operates at its full 2.4 GHz Turbo Boost for the first minute or so before dropping to a steadier 2.2 GHz. Core temperatures reach a bit under 70 degrees C. With just FurMark active to stress the Nvidia GPU, the graphics core operates at a steady 1124 MHz according to GPU-Z with temperatures plateauing at almost 80 degrees C.

Full stress with both Prime95 and FurMark active for one hour will drop the CPU to the 1.7 - 2.1 GHz range and the GPU to a lower 849.2 MHz core clock. CPU temperatures also reach a hot 84 degrees C. Despite these unrealistic conditions, the CPU never drops below its core 1.7 GHz base clock, though the GPU core does suffer slightly. Fortunately, a quick 3DMark 11 run immediately following the stress test shows no drop in final scores and no throttling issues. Both the CPU and GPU fare much better in a Unigine Heaven stress test as the CPU is able to maintain higher Turbo Boosts more consistently while the GPU runs comfortably at 1124 MHz.

Running on battery power shows no ill effects on CPU or GPU performance. A 3DMark 11 run on batteries reveals comparable final scores to the same run while on mains.

Battery Life

The integrated 4-cell 56 Wh 3785 mAh battery module is not user-removable, but it is larger in capacity compared to the 48 Wh module in the 12-inch ThinkPad Yoga, the 48 Wh module in the ThinkPad T440, and the 48 Wh module in the Sony Vaio Flip 14A. The Dell XPS 13 houses a 55 Wh battery despite its smaller screen size.

Battery life is good overall with a runtime of just over 5.5 hours with the Balanced profile active, dedicated GPU inactive, and the screen set to 150 nits (setting 6/10) while running our looping browser script. If sitting completely idle on the desktop with the Power Saver profile active at minimum screen brightness, the Yoga 14 can last for 11.5 hours. Lenovo promises up to 8 hours of constant use, which may only be attainable under very light loads and more reserved power settings.

WLAN runtime is about an hour longer than the ThinkPad T440 and half an hour longer than both the T440s and Sony Vaio Flip 14A. The differences aren't as wide as we had hoped, so a full day of use without needing to recharge is still risky with the Yoga 14 despite Lenovo's 8 hour runtime claim.