FWIW I just tried to update my XP Pro 32 box with an HD 5830 GPU to the latest drivers and it resulted in a BSOD. I even redownloaded the driver and tried it again. Same result.
Here's the reported error.

On Sat 5/12/2012 1:31:10 PM GMT your computer crashed
crash dump file: C:\WINDOWS\memory.dmp
This was probably caused by the following module: Unknown ()
Bugcheck code: 0x19 (0x20, 0xFFFFFFFFE10E1B08, 0xFFFFFFFFE10E1BD8, 0xC1A0401)
Error: BAD_POOL_HEADER
Bug check description: This indicates that a pool header is corrupt.
This appears to be a typical software driver bug and is not likely to be caused by a hardware problem. This might be a case of memory corruption. More often memory corruption happens because of software errors in buggy drivers, not because of faulty RAM modules.
A third party driver was identified as the probable root cause of this system error. It is suggested you look for an update for the following driver: Unknown .

Reverted to 12.1 and all is well again.