Windows won't start

[Itz.Flowers]

I got an old dell optiplex 790 a couple of weeks ago, put in a new power supply, graphics card, and an ssd. I've been playing games on it for a while and it's been working great. Today I moved it to my office, and now it won't boot to windows, just showing a black screen with a blinking typing indicator in the top left corner. There are no other messages. The boot screen shows before that blank screen, however, and the f12 menu doesn't show any irregularities. When I remove the boot drive it says it's missing, but won't boot when I plug it back in. I've already tried removing all peripherals, unplugging all the other drives, checking to make sure if everything's plugged in, and violently pressing all the buttons on my keyboard and mouse. All help is appreciated!

[Nord]

Sounds like a dead  C; drive.

 

Put in a different SSD/HDD and try to install windows on it - or simply check the drive that you are using now on a different computer (as D; drive obviously) inside windows for errors.