I have a relatively new gaming computer on my workbench which wouldn’t start up for the owner. When I was on-site, I tested the power supply and it failed the test. The owner said just take it with your and fix it.
I ordered a new power supply and when it arrived at my door, I disconnected the old one and connected the new one. There were a lot of extra fan cables since it was a gaming computer to keep it cool. At first I couldn’t get it to power on and I seriously thought the power supply was DOA.
I gave up for the day Wednesday and on Thursday I tested the Power supply and it passed. It actually started up another computer when I moved and reattached the connectors! So I know the new Power Supply is fine. Later after hours of testing I found out the CPU fan connector on the mobo shorts out the power supply and shuts it down. when I leave this out of the circuit, the power supply stays on and I actually get a video signal from the DVI video port.
Now I have to get the computer case fans to run and I’m going to need to re-wire them. The original builder of the computer used these old floppy drive connectors and the new power supply doesn’t have a cable for them.
I’ll keep you updated on the progress on the gaming computer who doesn’t like power supplies!