You could run the two OPUSes together, as long as you are not using them to power the motherboard. You can use them to power seperate devices, i.e. OPUS 1 for the motherboard, and all the peripherals plugged into it, like video card, sound card, other PCI components. The second one can run the IDE components, and all the other peripherals.
2000 Subaru OBS
Dell P3 @ 900 Mhz
7" Lilliput TS w/DigitalWW in-dash mount
80GB External HD