PC won't turn on after cleaning. Cause?

Question

Computers

I cleaned the PC system unit, after that it stopped turning on. I tried to reset the CMOS BIOS - no result.
The next day I turned it on - it turned on with a message that the BIOS checksum was not correct, there was a choice to load the default values, Windows started to load, but on the splash screen (where the black screen and the inscription windows) artifacts appeared at the top of the screen (red dots), I pressed reset - > loaded correctly worked for 15 minutes, the video signal disappeared. Now it does not turn on (the fans are spinning, the indicators are on, there is no signal on the screen), the POST procedure does not go through (there is no sound), but if you remove the RAM, it emits 3 beeps (AMI BIOS).
Is it really something on the motherboard burned out from static?
I cleaned it a year ago, it was the same, the next day it turned on and everything worked correctly.

Answer 1

I advise you to disassemble (remove the power wires, remove the video card, additional sheds - everything except the cooler and processor.), blow through the contacts, and reassemble. Perhaps dust has got on the contacts in the grooves, or a wire is coming off somewhere, or something is not fully latched, etc. Carefully inspect the iron when you reassemble - all contacts, all wires, etc.

Answer 2

everything can be.
If you do not have the skills to identify breakdowns, then you should not clean it yourself.
Check all connections again.
Incorrect BIOS checksum - apparently the battery was removed, or it is already dead.
Artifacts - apparently the video memory is buggy.

Answer 3

Unfortunately, it is not known whether the built-in video adapter is used or whether it is an external one.
1. If an external video card is used and the motherboard has a built-in one, then pull out the external one and see if the computer turns on on the built-in one.
2. If there is no built-in one, then you need to check if additional power cables are inserted into the video card; is the video card in the slot exactly; whether there are any elements knocked down during cleaning on the video card; throw a test video card borrowed from someone.