[KLUG Members] Power supply requirements?

[Bruce Smith]

I've proved the concept by building my own Linux based PVR (mythtv.org)
and I like it so much, I'm going to spend the money to do it right now. 
This involves getting rid of the big full tower case setting next to my
TV set and moving the guts to a nice small case (about the size of a
VCR) and putting it in on a shelf.

All I need in this PVR box is a fairly fast CPU (probably an Athlon), a
DVD drive, a video capture/tuner card or two, and one BIG hard drive. 
My question is how big of a power supply do I need?

Finding small cases is easy, except most come with small power supplies
too, in the 200W - 250W range.  Is that sufficient for this system?
It seems like I read something a long time ago that said you need a 350W
minimum for an Athlon (but I could be wrong).  Help!

 - BS