Originally Posted by
kalniel
From what you were describing it sounded like you couldn't even boot up, but you can actually run for a while sometimes?
GPU-Z and rivatuner have monitoring options, but if the stability is worse than it used to be then something has changed - could be something as harmless as dust, or you might have actually damaged something electrically or caused a soldier join to become fragile etc.
Or you could have just corrupted drivers or something related deep in windows - so you could re-install windows and then use the driver CD etc. just as you did first time around.. but it's probably easier to rule out the hardware via replacement/testing in another computer.