higher-end gaming rig PSU needs

[SuperSubZero]

How much power would a rig like this need:

P4 2.6-2.8ghz (w/HT, not necessarily Prescott)
Radeon 9800 Pro
1 Hard Drive (probably 7200rpm)
1 DVD-ROM drive
Optional add-on sound, like Audigy2, tho integrated would work too.

I have been debating trying to squeeze these parts into a micro-ATX case with an i865 board, but my main concerns are airflow (which I can probably handle) and the PSU. I don't know what kind of M-ATX PSU's are around nowadays, and the largest ones I can find are like 265W or so.

This wouldn't be overclocked.

 

[Nazo]

Generally everyone recommends a 350W as almost just a habit. I suppose it might be possible for someone to get by on just a 300W even. If I were you I would try to find more than 265 certainly though. For one thing, if you even just try to add more fans or something you will be running into problems. Heck, I have a 350 and I've managed to get rather extremely close to the edge of my system's power. I don't have too much more than you in fact. My main problem is all the fans together draw enough power that I'm getting close to the limit. If I were you though, I would assume nothing under 300 would do and possibly I wouldn't count on that.