problem with graphics freezing

[ashagplz]

ok this is puzzling me a bit. While playing games and only while playing games my computer is freezing. Well i will expand, i had a 8800 gtx which played company of heros just fine, but every so often the game wud freeze and i wud hav to click anywhere on screen to get it back. Then yesterday the game froze totally that i had to force a shut down to get back out of the game. Well when trying to reboot the bios wud not post. So i swapped out the 8800 (fan was working) for a 7800 gtx. The pc then booted fine. Thought maybe the other card was just loose so put the 8800 back in and the pc wud not boot again giving a bios fail beep. Put the 7800 back in and booted fine. Tried playing coh and blow me same problem, game froze so bad i had to force shutdown, but it did reboot. Cooling seems fine to me with 5 fans in a big coolermaster case. Seems puzzling that the 8800 suddenly wont even boot yet i still get a freeze with the 7800 in that game. Oh when the 7800 forze the monitor went off showing no signal.

Core i7 940
Gigabyte EX58-UD4P
OCZ 3PC3-12800C8 1600MHz Gold (3x1GB)
Be Quiet PSU Dark Power Pro 1000W

 

[varkanoid]

Try swapping the lead from PSU that supplies the PCI-E connector for the other PCI-E Connectors ?

 

[ashagplz]

i updated the drivers and put all fans into high mode and the 7800 played coh ok. Weird that the 8800 wont even boot now. yeah i cud try changing the leads i guess it cud be power related. The 7800 will boot even without extra pcie connectors, wonder if thats the case with the 8800.