Hello, I installed a new 6850 card and plugged in two required additional power cables from my old Antec EA-500D 500W PSU. I managed to install drivers and run unigine benchmark but 5 minutes later the screen went black and I couldn't get Windows to boot for 5 minutes after using the power button to turn it off. I tried changing the power cables but the screen always locks up after a while (especially after a benchmark). The graphics card requires a minimum 500W PSU with 12V 40A rating, but I don't know how to check for that rating. Is my PSU too weak? What should I get instead? Or could there be some other problem? My old card was a 5750 radeon and worked ok.
Thank you for your answers, I really appreciate it!
I did not remove the old drivers, I should probably do that because the screen went blank half a minute after the benchmark, while in... Windows, just surfing (i guess Flash could cause the crash).
I assumed the problem was hardware because Windows didn't boot up after I unplugged everything for about 10 seconds, and also I think I can hear a strange sound when the crash happens.
Is it enough to just uninstall Catalyst and remove drivers from device manager, or do you recommend some 3rd party program? I could just reinstall Windows...
I have 64bit Windows 7 (on an older generation i7 with 6GB of ram and 1TB caviar black, there are no other power spenders). PSU is actually not that old, about a year and a half (SC2beta timing).
I didn't try any gaming yet. Finally, about temperatures... I just ran catalyst control center and went to overdrive tab. Everything was disabled there, and the temperature reading was 60 C with about 40 % fan speed, 10 seconds after the benchmark... and then I start using the PC normally and the crash happens between half a minute and two minutes later. So I guess it's not temperature related.
Ok it seems to work ok now, I even got 10% better results in the benchmark. I couldn't find working link for drivesweeper, and its been discontinued so there's no win7 version. I just put the old card in, uninstalled all ATI software, restarted to safe mode, uninstalled and deleted the drivers, replaced the card, uninstalled drivers again, and installed the latest catalyst. The network cable was unplugged the whole time so windows wouldn't try to be helpful with automatic driver updates.
And it seems to be very stable
Thank you for your help! I saw the 22A mark on the PSU and was preparing to buy a new one, didn't know I should divide 444W with 12V to get 37A.