New build help please

Dec 1, 2018
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I’m having trouble firing off my new build, I’ve takin everything out except the processor, the power supply, a stick of ram and the motherboard.

I flip the switch to the power supply the motherboard light comes on(not the debug light) and I press power on the tower and everything lights up for half a second and immediately shuts off, I then have to unplug the power supply and plug it back in for the motherboard light to come back on, can anyone help me? This is my first ever build
 
Dec 1, 2018
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I tried my old PCs power supply to see if that was the problem but now when I plugged it back in to the old pc, it doesn’t boot up, runs for 30 secs and shuts off
 
Dec 1, 2018
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The motherboard AND the debug light up for about 10 seconds with just the mobo cord in, then it resets and repeats but when I plug the cpu cord in, it’s immediate shut off, no reset