I personally dont think that the drivers will cause crashes like you described.
you still havent told us what your gpu temps are at load or at idle, that would be a start. I personally experieced artifacts and crashes at anything over 90c, check the temps if you want help
Look, it's definitely not LFS' fault, so either get that card replaced or find out what's wrong with your hardware yourself. Remote diagnosis only goes so far...
He has a mate who knows alot about pc's who upgraded his, i dont think the drivers for the mobo are installed, and the monitor might be plugged into the motherboard not the card, i dont know, but his friend left a wire near the gfx cards fan, it sucked it in, and broke the fan in half, what did his mate do? put another case fan in and said it was fine to play games on!
Have you been to his house to fix it then? Or is this a translation of a PM you received? Sounds like his PC knowing friend is an eejit. In some countries they'd cut your hands off for being so ignorant!