NVIDIA graphics drivers to go multithreaded
 

Out of curiosity, I asked de Waal why NVIDIA's drivers don't already take advantage of a second CPU. After all, the driver is a separate task from the application calling it, and Hyper-Threaded and SMP systems are rather common. He explained that drivers in Windows normally run synchronously with the applications making API calls, so that they must return an answer before the API call is complete. On top of that, Windows drivers run in kernel mode, so the OS isn't particularly amenable to multithreaded drivers. NVIDIA has apparently been working on multithreaded drivers for some time now, and they've found a way to fudge around the OS limitations.

http://techreport.com/onearticle.x/8459