Rich,
  I finally got it. Thanks for all the helpful suggestions . For anyone else that has a similar problem, this is what I found.   I ran the driver test as suggested. The test actually didn't look that bad, but when in the Mach  window under diagnostics it showed the same problem with erratic pulse frequency. I  decided to load the special driver found in the Mach folder.  This fixed my problem. My pulse frequency is now locked in at 25382 and I believe this is a great number. I'm glad I didn't give up and go and buy another computer.   Thanks Rich, and all others

Craig