Less common G5 issue?

[one1]

I have a 17" iMac G5 out in my garage I use to surf when I am working on things outside and lately it has been going to a blank screen with rushing fans after it has been on for several hours.

I cleaned the lower CPU fan, checked the capacitors, basic inspection and cleaning revealed no obvious issues.

After unplugging the unresponsive computer and plugging it back in it seems to run fine for an hour or sometimes several hours before going back to a blank screen and full speed fans.

What system tests can I perform to determine what may be the issue?

~TIA.

 

[NeverhadaPC]

check for a lose cable connections inside the iMac --- that could explain the blank screen.
fans going into super-drive generally means overheating... but I would venture to guess you might have a faulty sensor that misreads temperature...

In the end, who knows with G5's... I have an iMac G5, whose Video card got corrupted after 3.2 years, and, ever since, I have been using an external monitor. I never had the fan issue.

 

[one1]

Thanks for the response. I have since noticed it only does it at idle. I do not have any CPU intensive screen saver enabled or such. In activity monitor I don't see anything out of the ordinary. I was successful at using it for several hours the other night without fail until it sat alone for 30 minutes.