well...this is an update...after MUCH research on the mp3car.com forum. i have come up with...

amd xp-m 2400 or 2200(35w)
asus a7n8x deluxe (~25w)
2.5" 60gig hd (5w)
geforce3 ti or ati 9200 (30)
512 ddr(10w)
cpu fan(3w)
keyboard(2w)
mouse(1w)
2 usb devices(10w)

thats 146W exactly at peak enough for a 150w opus