PSU stands for Power Supply Unit. How are you monitoring CPU usage? Which OS are you using currently?
If you're using Win98 try this; click on START>>SHUTDOWN>>RESTART in MS-DOS MODE... once you're in the DOS screen you'll see "C:\WINDOWS\>blinking cursor". Type"cd.." without the quotes and you should see C:\
Now at the PROMPT or cursor type "scanreg/fix" without the quotes and as soon as it finishes, at the PROMPT again type "scanreg/opt" without the quotes and as soon as it finishes you'll see C:\
This time you type "exit" without the quotes and windows will boot.
If your REGISTRY was damaged, that should fix it. Do a DEFRAG and then see if that made a difference. If it didn't, only thing I can think of is your PSU not handling the load. Then again it could be a lot of other things.
Let me know if that helped.
<A HREF="http://www.anandtech.com/mysystemrig.html?id=23810" target="_new"><font color=blue>My System </font color=blue></A>
<b><font color=blue>VAGABOND<font color=blue></b>
<b><font color=blue>veni,vidi, and ended up in THGC<font color=blue></b>