Digidesign AM3 is neither Direct X compatible nor do they have GSIF drivers.
AM3 will not support Giga in the near nor the far future.
To make Giga work on your system you need to get an additional card which is either Direct X or has GSIF drivers.
Simple answer is yes.
Just a reference, I used to have three soundcards in same system. They\'ve added more latency to the realtime recording and each one would used about up to 5~15% system\'s resources (CPU, MEM).
Make sure that they are PnP compatible (ISA/PCI), and they are own DMAs/IRQs (no conflicted or shared IRQ/DMA).
Conclusion: best performance for giga, see the hardware recommendation at Nemesy. The compatible GSIF with multiclient soundcard is functional like the multiple soundcards.