XPS 8950, turns on after I turn it off, no display or keyboard response

I have an XPS 8950 Desktop. My computer was having issues before, so in order to fix it, we downloaded the windows installation media onto a USB, and set the BIOS Boot to the USB. The computer then was scanning the hard drive when we turned it on again, but froze at 85%. I restarted it, and it messed up. Keyboard won’t respond, there is no display, and the computer keeps turning on right after I turn it off. What do I do? I don’t have money to fix it.