This is usually heat related, defective hardware, memory or even processor though it is "possible" that it is driver related (rare). Remove ALL power and reseat all cards, memory and cables (on both ends) - actually remove and replace - do not just snug. Make suremthe system has adequate ventilation - add a small fan blowing into intakes. Carefully inspect the motherboard and other cards for damage. Pay attention to the fatal hardware error implication. You may need a real computer shop (not leeks and peeks at a BestBuy or other BigBox stores) or the System maker's Support.
Check the processor seating, heat sink, and the compound between the processor and the heat sink which are common causes.