My computer keeps crashing / locks up ,and I have to restart it ,I asked my geek Brother inlaw and he does not know why ,I just replaced the power supply cause my othe one die .This PC is 3 years old ,it has a first gen. P4 1.0 Gig and the old school intel 845 board ,We checked out the Hard drive and it works ok ,how can I check the mother board to see if it has issues ,or should I just build a new one ,cause they die about 3 years ..............................