Pc has power, black screen, keyboard lights up but has no input.

Jul 15, 2021
So my pc hasn't been used in a while and theres been alot of dust around. I cleaned it out but whenever i start it up i get a black screen the keyboard has power but there isn't any input. There isn't any beeps tested the monitor on another machine and it works. I tried another monitor as well. I tried using the motherboard hdmi and the graphics card to no avail. Also sometimes after shutting it down the keyboard light stays on. Then i unplugged the keyboard and the mouse lit up.
I really don't know what wrong.
Any advice would be great.