Vista drivers: coding them is harder than it sounds

Both AMD and NVIDIA are having trouble making good Vista compatible drivers for their graphics cards. The main problems lie in multi-GPU support. While both companies will certainly have a driver for Vista x86 by January 30th, it will be harder to support than the XP version. NVIDIA has also hinted that they will work on an x64 driver after making an x86 driver, instead of doing both at once.