...and if you don't have one of these, there's bads of room for a generic +12v / +5v PSU (it makes all its other rails from these voltages). Do check the voltages coming out of the PSU before replacing it though, ISTR there was some heinous silkscreen mislabelling on the central main board (like 12v labeled as 5v and vice versa or something). Might have just been the dev units though... even though they maybe outnumbered the production ones

I suspect +12v/+5v @ enough to power HDD and CDROM (then add 500mA to each for the main board/display power) would do fine.

Hugo