Question Desktop won’t display on my monitor

[Redneck01]

I’m currently restoring an old windows 8 computer that has been outside for a little bit and it is turning on but not displaying anything on the monitor. I have replaced the mother board battery and moved the ram around. Any other suggestions?

 

[rgd1101]

full system spec? include make and model of the psu

 

[Redneck01]

full system spec? include make and model of the psu

Man I don’t know any of that, at all. I’m new to the computer scene