|Usually when a PC doesn't POST (Power On Self Test), the CMOS (which contains the BIOS - Basic Input Output System) is corrupt.|
You could try CLEARING the CMOS. It could be a memory issue, or power supply maybe, or CPU/Heat sink issue, but chances are it's the CMOS.
Years ago you could just replace a removable CMOS chip on the motherboard, now they socket & solder them into the motherboards so you have to replace the whole motherboard (probably so they can sell more motherboards?).
Just another stupid saying...