Has anyone had any success, possibly with the 830 drivers, getting things working on an Intel 815 chipset? I have no idea how different these two chipsets are.

Hi, there.

I doubt anyone will ever get this chipset working for one simple reason:
This chip is for use with Pentium III and Celeron with Socket 370, which simply do not support SSE2, let alone SSE3.

I know this because I have one of these. Asus TUSL-2.

Cheers.