The most common things I run into are:
1. There's an extra mounting post under the motherboard.
2. The PSU gave up.
3. There's some other shorted item.
To find it I often have to put the motherboard and PSU on cardboard and try the power up test there.
Bob
I recently updated my motherboard, CPU, Ram, and HDD. Recently after I was able to start it up but it required some fiddling to get the power button to light up to be able to turn it on. I was then forced to move and I am now unable to get any sign of life. When I switch on the power supply I get a faint consistant tick. I have read that my case, Cooler master cosmos S, has button problems. Does anybody have any ideas on what the problem could be? What are ways to test the psu? Is there an easy way to bypass the button? Any help is appreciated. Thanks.

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