Psu+mobo+cpu/hsf.
Nothing else connected or plugged in.
Short the power pins on the mobo for a second.
If it does not power up your down to 3 parts.
I built my PC about 8 months ago and everything worked fine. I moved to Korea, military so voltage is still 120, and now it randomly won't power on. The only upgrade I've installed is a wireless card, but it worked fine long after I installed the card.
The PC does not power on with the power button, bypassing the power button and "hot wiring does not power the PC. I can hear an external HDD receive power when I plug in my computer but no lights on my board. At times removing the RAM would allow my PC to power on but that no longer works. I've tried removing all connected devices minus keyboard and mouse and nothing. At times it repsponds to the power button and boots, and others it doesn't. Completely random. Also of note, the last time it booted the screen went gray and Windows wouldn't load.... Shut her down and now nothing. PLEASE HELP, in lost now

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