I would be guessing if someone used a 200 Watt supply and a Nvidia 970 video card. That would cause what you noted.
Bob
So yesterday I tried building my own gaming PC, and things didn't quite work out. I used a video to build it following all steps. This is my first build and I'm not sure as to what the problem is. When I turn the computer on I just get a black screen on my monitor. I'm not sure as to what the problem could be but the graphics card spins up then stops and repeats that (which I'm not sure if it is supposed to do that) the cpu fan is not running when I turn it on, although it is plugged into the motherboard and has power. The cpu fan only spins up when I turn it on/off and only does so briefly before stopping, and none of any of the USB ports are working. Any help is appreciated

Chowhound
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