Graphics card turns off...

yumpum

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Apr 16, 2010
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Hey all, Today I built my first new system... woohoo! Anyway it includes a HD 5770, which when I put under a stress test will turn off (Monitor saying no signal) after around 25 seconds. I realise this is either heat related or power problems.

It approaches 80C when it shuts off, so I was wondering is it possible it has a built in feature to turn itself off to prevent damage?

As for the power supply, I have run my CPU (phenom ii x4 955) on full load for 10 minutes without a single problem. Also I am using a 500w PSU, even though a power supply calculator reckons I need 250w? I am fairly sure that has to be innacurate, but I cannot find any other explantions.

Any help please?