Did you examine the capacitors on the logic board for corrosion and/or swelling? Do a search on this site for "bad cap", there are a plethora of answers. Here's one: http://www.ifixit.com/Answers/View/1441/iMac+G5+20%22+1.8GHz++no+display
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Did you examine the capacitors on the logic board for corrosion and/or swelling? Do a search on this site for "bad cap", there are a plethora of answers. Here's one: http://www.ifixit.com/Answers/View/1441/iMac+G5+20%22+1.8GHz++no+display