I'd try another video card. This doesn't look like a software or driver issue.
Kees
It's not until about 2 weeks ago I installed sims 3 on my computer, then playing about 3 days into it my computer suddenly turned off, when I turned it back on, the screen kept saying no signal (it's plugged into my tv) trying to turn it off and on again it started beeping a few times it wasn't working for a few days then it suddenly started working again although it does go off now and then for a while, I did a system restore before installing sims 3 I thought it was working again then it kept going black on the user screen sometimes, and it still was turning off (usually when the fan came on) and displaying no signal. It works sometimes if I leave it for a while. Please help it's been driving me mad.

Chowhound
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