just because if the drivers reinstall does not work doesn't necessary make it a hardware issue. NVidia is known to have the worst drivers out with problems with crashing, ever since Microsoft got harder on drivers after vista and up with tdr (which should be turned off because 90% of the time this is what cause gcard bosd and resets everytime). depending on the error he is getting and if his chip/gcard is not overheating its most likely tdr problem which can be turned off in the registry.