My Lenovo T61 is reporting BSOD with NMI Parity Error. After a lot of sleuth work, I've established that it's the Nvidia GPU that's overheating and causing this error. Others have reported this. The cooling is just adequate for a non-GPU equipped T61, but when the GPU is added and the cooling fan starts to run slower (the main bearing in mine has gone, it rattles and screeches) the GPU overheats and the system goes BSOD.