Microsoft Surface Book (Core i5, Nvidia GPU) Notebook Review

The design may be minimalist, but its defined edges and rectangular look are unmistakably Surface and contrast very well to Apple's current crop of MacBooks. Its unique property is the taut fulcrum hinge, which is somewhat similar to Lenovo's Watchband hinge for the Yoga 3 Pro and is Microsoft's answer to creating a stronger connection between the detachable base and display. 2-in-1s like the Surface Book are notorious for having weak, top-heavy, or rocking hinges due to the heavy display portion, but we can now say with certainty that the Surface Book offers one of the most stable solutions that we hope to see mimicked from other manufacturers.

It's not perfect, however, as the display can still rock back-and-forth just slightly and the maximum angle is only up to ~130 degrees. The notebook cannot close completely and leaves an overt gap that makes the device look thicker than it actually is. This also makes us less comfortable carrying the device in a backpack or bag without a proper cover as small items can easily fall in between.

Keyboard

Aesthetically, the keyboard could easily belong on a Chromebook because of its simple appeal and layout. In terms of usability, the keys offer an excellent combination of travel and tactile feedback for a surprisingly comfortable typing experience. Typing feels roomy (17 x 17 mm QWERTY keys, ~2.5 mm spacing) and with almost no clatter. Individual keys are stiff and do not wiggle in place as may happen on less expensive Ultrabooks.

As great as the backlit keyboard may be, it is oddly missing brightness controls. There is no Bluetooth connectivity for the dock as it relies solely on its pins for communicating with the tablet. The Up and Down Arrow keys are halved in size, softer in feedback, and are less comfortable to use.

Finally, the proper way to use the keyboard dock is to power on the tablet while it is connected to the dock. Attaching the tablet to the dock after powering on the tablet will temporarily disable the keyboard, touchpad, and USB ports. This behavior is very strange and we can only assume that this is a bug with the system's automatic detection. The dedicated key to properly detach the tablet may sometimes be unresponsive as well.

Touchpad

With a surface area of 10.6 x 7 cm, the Surface Book touchpad is large considering the screen size. This makes for easier multi-touch gestures and basic scrolling with smooth gliding properties from edge to edge. Business purists may lament the fact the there is no TrackPoint or dedicated mouse keys. More "traditional" business notebooks from the ThinkPad or EliteBook series are faster and more accurate to control if no external mouse is available.

November 3, 2015 update: There have been multiple reports of the touchpad misbehaving during use. We can confirm on our test model that there is indeed a responsiveness issue, specifically around the edges. The entire surface can sometimes become unresponsive if gliding from the outside towards the center, but not if gliding from the center towards the edges. The problem occurs under very specific circumstances and appears to be software-related rather than a hardware issue.

Touchscreen

The 5-point capacitive touchscreen is made easy to use by the relatively lightweight tablet and narrow bezel. We experienced no responsiveness issues whilst using the Surface Book in this manner. We can, however, mention that automatic rotation can only be toggled through software. Competing convertibles like the Lenovo Yoga 3 Pro offer a hard toggle switch on the edge for convenient access, which can be very handy when sharing content with others in tablet mode.

Stylus

The included Surface Pen is identical to the one for the Surface Pro 4. Anyone who has used the stylus for the Surface Pro 3 will be instantly familiar as it provides the same number of functions and 1024 levels of pressure. Its wide diameter already makes it one of the more comfortable styluses to use as it better mimics the size and weight of a typical ballpoint pen.

Color space coverage is a measured 64 percent and 96 percent of the AdobeRGB and sRGB standards, respectively. While not important for emails and word processing, the near 100 percent sRGB gamut is vital for digital graphic artists. This is comparable to other notebooks with high-end displays including the Toshiba Kira series. Standard IPS panels typically cover only 60 to 70 percent of sRGB in comparison.

Further analyses with an X-Rite spectrophotometer reveal very accurate colors and grayscale with no end-user calibration required. The MacBook Pro Retina 13 does come in just slightly more accurate in terms of DeltaE2000 deviations. Colors are shown to be a bit less accurate at higher saturation levels, which suggests less-than-perfect sRGB coverage despite Microsoft's claims of 100 percent sRGB.

Photosensor measurements reveal no use of pulse-width modulation. Black-white response times are the typical 7 - 8 ms while grey-grey rise and falls times are slower at about 20 ms and 29 ms, respectively.

Outdoor usability is very good when under shade or an overcast day. Maximum brightness will not artificially drop if disconnected from mains or the keyboard dock. The glossy Gorilla Glass 4 cover works against the screen with heavy glare present. It's possible to comfortably view content under direct sunlight assuming that the glare can be avoided.

Viewing angles are excellent due to the underlying IPS panel. Colors and contrast do not significantly degrade even if viewing from extreme angles or orientations. Relative brightness remains very stable regardless of the angle.

As one of the first new notebooks to be equipped with the 2.4 GHz Core i5-6300U, raw performance in synthetic CPU benchmarks leaves a very positive impression. The Surface Book maintains healthy leads over common ULV processors of yesteryear including the i5-5300U Broadwell and i5-4200U Haswell by up to 14 percent and 27 percent, respectively, in multi-core CineBench tests. Single-core gains over Broadwell are smaller due to smaller differences in Turbo Boost speeds. This is still a dual-core CPU, however, so quad-core processors like the powerful i7-4720HQ will significantly outpace the i5-6300U in multi-threaded operations.

More technical information and comparisons on the Core i5-6300U can be found on our dedicated CPU page here.

PCMark 7 ranks the Surface Book very highly for a detachable. Its final score of 5135 points is essentially on par with the older gaming Schenker XMG P722 and its GTX 680M SLI and the Asus ZenBook UX302. PCMark benchmarks tend to heavily favor SSD-based systems and the new NVMe SSDs already rival systems equipped with SATA III SSDs in RAID 0.

Subjectively, system performance is almost instantaneous when navigating or launching applications. Detaching the tablet portion can feel a bit clunky, however, as it is completely software-driven. The tablet can only be removed once the onscreen popup message says it is ok, but the message will unnecessarily linger for quite some time even after detaching from its base.

Microsoft is advertising its optional Nvidia Maxwell GPU with no hard specifications or numbers as it is likely a customized chip designed specifically for the Surface Book. Thankfully, a quick look with GPU-Z reveals specifications unlike those of the GeForce 940M including a total of 384 Unified Shaders and a 64-bit bus width. Pixel fillrate (15.7 GPixel/s 940M vs. 15.3 GPixel/s Surface Book), Texture fillrate (31.4 GTexel/s vs. 30.5 GTexel/s), memory clock (1001 MHz vs. 1252 MHz), and GPU clock (980 MHz vs. 954 MHz) are also nearly identical between the two GPUs. The biggest difference is that the Microsoft solution uses 1 GB GDDR5 VRAM instead of DDR3, which should theoretically give it the edge in modern games.

Indeed, 3DMark benchmarks show exactly as predicted as Cloud Gate and Fire Strike scores are about 20 percent ahead of the Nvidia 940M and Intel Iris Pro Graphics 5200. It's still quite far away from the 950M, however, and is unfortunately closer to the 940M than it is to the 950M in terms of raw performance. Nonetheless, it is a huge upgrade from the integrated HD 4000 or HD 5500 commonly found on affordable Ultrabooks.

The Microsoft notebook holds up extremely well to stress tests. The CPU itself is able to maintain a consistent Turbo Boost of 2.8 - 2.9 GHz compared to its base 2.4 GHz clock rate when running Prime95. The Nvidia GPU throttles just slightly under Furmark from its base 954 MHz to a steady 823 - 888 MHz range. Running both Prime95 and FurMark simultaneously will throttle the GPU further while the CPU is unaffected. The catch is that CPU temperature can reach 90 C under these conditions compared to ~75 C for the dGPU.

Unigine Heaven stress is more representative of real-world loads. Constant CPU Turbo Boost is not necessary under such loads, so the CPU will range from as low as 500 MHz up to 2.9 GHz as needed. Core temperature is consequently much lower near the 60 C range. The GPU is able to run consistently with Boost at 993 MHz.

Running on battery power will not reduce GPU performance, which is quite uncommon for a detachable. CPU Turbo Boost, however, will occur less frequently. A 3DMark 11 run on batteries resulted in Physics and GPU scores of 3541 and 2529 points, respectively, compared to 4199 and 2548 points when connected to mains.

The primary module in the tablet carries a capacity of 18 Wh while the secondary battery in the docking station holds 51 Wh for a combined total of 69 Wh. This is higher than most other 13-inch or 14-inch notebooks where 40 to 60 Wh batteries are the norm with the exception of the 75 Wh battery in the MacBook Pro Retina 13. The modules are not removable in either case. Our data below reflect runtimes in minutes with the docking station attached.

Runtimes on the Surface Book are good, though not fantastic by any means. Our looping WLAN test runs for just under 7 hours until automatic shutdown. Certain competing models can last for at least hour or two longer than the Microsoft notebook under the same testing conditions despite carrying lower capacity batteries. This may be attributed to the Surface Book's lack of Optimus as there is currently no official way to disable the dedicated GPU when the keyboard dock is connected.

It's worth noting that when attached to the docking station, the secondary battery is drained first until it reaches 40 percent capacity. If below this point, the tablet will draw power from both the primary and secondary batteries simultaneously until automatic shutdown. This behavior contrasts how HP utilizes its dual batteries in its own Split x2 detachable where the secondary must be completely drained before drawing power from the primary. Charging the Surface Book takes roughly 2.5 to 3 hours total for both the dock and tablet. Unfortunately, the dock cannot be used to charge the tablet and vice versa if no outlet is available.

Surface Book SKUs with no dGPU will ship with a 36 W power adapter while SKUs with the Nvidia dGPU will have a 65 W power adapter. Both adapters include one built-in USB port for charging other devices.