On 18 Sep 2006 at 20:26, Dave Schroeder wrote:

> "After my PC has been on a few minutes, the humming is so loud I hear
> it several rooms away.  Then it revs up like it's going to take off,
> then backs down.  I know that's not right.  " 

  Hard drives and fans generally run at a constant speed, and so their noise 
tends to be constant too.  This "rev up" sounds like what some machines I've 
worked with do in order to determine what CD/DVD (or, occasionally, floppy) 
is in a drive.

David Gillett

                  Visit our website regularly for FAQs,
               articles, how-to's, tech tips and much more
                          http://freepctech.com