Bob Knowlden wrote:
I doubt that you'd need a new case. Most of the ATX cases I've used were
also compatible with MicroATX boards. I hope that you have documentation on
the case.

It's possible that you'd need a new power supply. The P5V800 MX uses a 24
pin ATX 2 power connector. You may be able to get away with one of the older
20 pin connectors. (It ought to plug right in, without an adapter.) I have
read of people doing that successfully, but it's not guaranteed.

You mentioned a P4 1.7 GHz CPU. I hope that you're not intending to use it
with the P5V800 MX. It's a LGA board (land grid array, Socket 775), and
incompatible with a Socket 478 P4.

Bob,

I would also upgrade my CPU to an Intel 820. I recently bought a new
400 watt power supply as I upgrade my GPU and my old PSU was not enough
for it.

Eddie