DPS will function with most onboard and PCI audio sound cards, with the following possible limitations:
On Windows 98 especially, many motherboards quickly run out of resources (IRQ) when having more than one soundcard added.
Two or more identical cards may be indistinguishable in windows, or DPS, or both. Avoid having two identical cards if you can help it. Where a Soundblaster Live! and a Soundblaster PCI may work together, two Soundblaster PCIs probably will not.
Neither Microsoft nor Soundblaster will support more than one identical card on the same machine.
We do not explicitly recommend sound cards as each system, and your requirements of it, are unique. We suggest you might like to look at the MAudio Delta as a possiblilty for avoiding some of the pitfalls above. This card offers several outputs and several inputs on the one card.
Other manufacturers may offer similar devices that you should consider.