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Apple iMac A1225 24" Delta power supply Has anyone out there ever had a power supply that powers the computer but not the display?????????
It was the GPU Got my Mini DVI connector and got the Mac to display onto another external display. Got another display and still nothing, got another inverter cable and still nothing. So instead of buying another GPU I bought another iMac that worked but had a yellow screen to test the PSU. Took the PSU out of the problem iMac and tried it in the newer Mac, and it worked. So I thought for sure had to be the logic board. So I got a logic board and replaced the old one. Still got no display. I had another GPU that I bought for another iMac that was older and the GPU didn’t work with it so I thought why not try it. And now I am posting this for the problem iMac display works good except its still yellow.
Of course. Different parts of the power supply can be lost. You may loose power to the hard drive or any of the components. We start by looking at the diagnostic LEDs. The 2007-08 models had a known issue of bad capacitors. China has been clearing their inventory of 10+ year old parts and you may be able to get a new one cheaply now.