Despite nVidia's success stories with desktop computers, its history in the mobile-GPU market is mixed. The company's chief rival, ATI, has been able to parlay its desktop technologies into mobile offerings more aggressively, and holds the lion's share of the market. But nVidia's new GeForce Go 6800 could put a dent in ATI's enviable position.

The GeForce Go 6800 is the first mobile GPU based on the GeForce 6 Series of desktop GPUs. It combines nVidia's UltraShadow II technology for Doom 3 with support for DirectX 9.0 Shader Model 3.0. The Go 6800 has 12 pixel pipes and comes at two different clock rates: either 275 MHz or 450 MHz for the "desktop replacement" version. This GPU has 190 million transistors. Running all of them at 450 MHz in a laptop could prove challenging, even for a large, high-end gaming notebook.

The Go 6800 performed impressively in our preliminary tests. We also got a chance to preview ATI's upcoming 12-pipe GPU, code-named M28. Set to be formally unveiled in a few weeks, the M28 also performed very well, and the two GPUs highlight their respective companies' strengths. The nVidia GPU dominates on Doom 3, whereas the ATI holds a small advantage on Far Cry.

nVidia hopes to grow its share of the laptop-GPU market dramatically. In terms of pure performance, the GeForce Go 6800 is certainly a step in the right direction. It faces tough challenges in the mobile market, however, mostly because of thermal and power constraints that limit its clock rates. Also, ATI's M28 is going to keep the race very close, and that chip's leaner transistor count may make it more attractive to laptop makers looking to control power consumption and heat output.