Selling out quite quickly, the well-received Surface Book from Microsoft has still largely remained a mystery in terms of its tech specifications. Microsoft has still not revealed the major components other than it will run an i5/i7 CPU along with an unnamed Nvidia GeFroce GPU. We’re now hearing reports that the unnamed Nvidia GPU may be some variant of Nvidia’s GeForce 940M.
According to the Nvidia Control Panel, the GPU will feature 384 CUDA cores clocked at 945Mhz. For memory, a relatively meagre 64bit interface connects to 1GB of GDDR5 at 5010Mhz for 40.08 GB/s of bandwidth. For comparison, the 930M has the same number of shaders but with a slightly lower clock rate and DDR3 VRAM that only gives about 16GB/s. The 940M, on the other hand, has higher clock speeds but is sometimes saddled with DDR3 and other times uses GDDR5.
It’s interesting that Microsoft went with a discrete Nvidia GPU of this level given that Intel’s latest Iris Pro iGPUs are quite competitive right now. In fact, the top Intel iGPU will probably beat out the Surface Book dGPU. The current configuration with the GT2 in the tablet side and the 940M does offer some power benefits as the weaker GT2 can sip power in tablet mode and move to the more powerful 940M once the extra battery from the keyboard gets into the fray. On the other hand, Apple does manage to use just the Iris Pro in their slim portables so it remains to be seen which solution is better.