Originally Posted by
Norman121
The fact that you are able to boot sometimes after moving the CPU might suggest that it is has become loose over the years. Perhaps try removing the heatsink/fan from the top of it, cleaning both that and the CPU, reapplying some thermal paste (if you have any) and then re-attaching it. If you can, make sure it holds tight to the CPU and motherboard (but not too tight).
Failing that, I'm afraid I'm running out of ideas. It may just be a case of wear and tear causing the motherboard to have problems. Sorry I couldn't be more help.