<snip>
I'm having problems booting from my Knoppix 3.1 CD - it always hangs during boot...
</snip>

Check your BIOS version -- upgrade it if necessary. It is a known fact that the VIA 686A Southbridge has problems, especially the early steppings, but the right BIOS can patch things pretty well. From a search on Google, there IS a "secondary channel DMA" problem with the 686A, but it may well be stepping-dependent -- that is, early versions of the chip are more likely to exhibit this problem than those manufactured later in the cycle.

Though this is slightly off-topic, it is still worthy of mention: DON'T upgrade the BIOS from a physical device, that is, a floppy or hard drive. I use the MSI technique:

1. Boot from a Win98 Emergency Boot Disk (either version). You don't need CD support. This creates a RAMdisk in memory.

2. Copy the flashing utility and the BIOS image (usually with a .BIN or .ROM extension) to the RAMdisk.

3. CD to the RAMdisk and run the flash process from there.

In a sense, flashing the BIOS "pulls the rug from under" the hardware, plus the floppy is too slow and error-prone. I have had the best results using the above technique.