Hi, so when I have the GPU pcie express power plugged in, my computer won't start at all, but when I don't everything turns on and the GPU fans spin. Any suggestion on what the problem may be? Some back story, this gpu was working fine just three weeks ago, got a cheap 2080ti, and recently sold since I realized it was overkill. The GPU is a radeon 6950, if that helps. 750W power supply.