Radeon 4870x2 won't run in 3D

[Guest]

Radeon 4870x2
Chietftec 650W for graphics, 400W for the rest
Cooler Master case
Intel Xeon processor
Asus P5Q-E
Win 7 x64

Hi everyone!
I'm having problems with my graphics card. Whenever I run something in 3D mode, the computer freezes and the display says "no signal detected". It happens in all types of games, even the ones that ran before extremely smoothly and are not much demanding.
I started with checking all the other components in diagnostics software and had no problems until selected 3D Graphics option. Then I changed the thermal paste and vacuumed everything. Nothing changed. Running the cooler on max speed doesn't change anything either. I have cleaned all drivers and installed the newest ones. I also have installed a new Win Vista x64 to be sure. Doesn't work.
Temperatures are not the lowest, but everything used to work a month ago.
Can you help me solving this problem? I'm ready to do almost everything with the card. I can't RMA it, because it's too old Would placing it in an oven work? Or should I start looking for a new card?

 

[viper_69]

Thats too bad sound like your card is goin sorry to say Im pretty good with this stuff and I would recommend everything you did besides trying to flash your cards bios if none of that works Im afraid you might be lookin at getting a new card if it was working just recently.....or for a long shot did you do a windows update then it stopped working?Sorry Im not too familiar with vista

 

[jsc]

If the card works in 2D but not 3D, you either have a power problem or the card is defective.

I notice that you have 2 PSU's shown in your system. Your problem could be there.

The Chief-tec, while close to being a piece of junk, if properly working, should be able to power your complete system.

Otherwise, it sounds like your card is dying.

Try the card in another computer with an adequately sized PSU to see if the problem is your card or the rest of your system.

If the card works, then try the Chief-tec by itself. If that doesn't work, try to borrow a good 600 - 650 watt PSU.

 

[viper_69]

+1 to jsc when buyin parts for your rig dont go cheap especially your psu. You can never go wrong getting a GOOD brand psu