Author: J i m s t e r
Subject: Unresponsive PC but CPU utilization OK
Posted: 04 December 2013 at 8:21am

50p - I was suffering from similar symptoms, with no obvious cause.  Try running eventwvr from a prompt, and seeing if you get any of these in the system log:

Kernel Processor Power (Error ID 37 in event viewer)

They were being caused by excessive dust on the processor fans/airways.  The proessors were getting mad hot and the o/s was slowing them down to stop them popping off the board.

Solution is to get a can of compressed air and blow it through the airways (WHILE THE PC IS OFF).

You can test if the processors are getting hot with freeware like Core Temp (google it).  I would say, as a rule of thumb, North of about 80c is too warm.

It's Vista so probably got at least 3-4 years worth of dust in there unless you've already eliminated this as a possibility.