Failing power supply

[Bob Mitchell]

I've got a 2 and 1/2 year old 7300 whose power supply seems to be failing.
It started when I got back from a trip to my parents at Christmas time, and
tried to power it back up.  It took me several tries to get the hard disk
started.  More recently, every time I power it up it takes 2-3 minutes just
to get the video and floppy running, let alone starting the hard disk.  In
addition, I'm getting far more random hard disk errors than I ever did
before, which I have heard contributed to a bad power supply.  The real
clincher was that my last electric bill (from just before Christmas to
early February) was 20% higher than it should have been, even though my
apartment has electric heat.

Anyway, my questions are:
  Does anyone out there have any leads on getting UNIXpc power supplies
replaced or fixed?
  In general, what does it cost?
  Assuming I have to take the power supply out to get it replaced, are
there any special precautions to take?  (I do know how to open the computer
up, I'm more worried about shocking myself or doing damage to the computer
in the process of removing the power supply.)

					Thanks in advance,
					Bob Mitchell.