I had a system with a knoppix derivative installed to the hard drive.
Worked great, upgraded it, etc. so, pretty much, straight-up
debian[-testing?] at this point.

Went and got an MSI 915G mobo, PIV 3GHz, bla bla. Moved the disk, and
now I can't get video, and when I try to boot 2.6, it just locks.

I was running 2.6.7-custom, so installed 2.6.8-686-smp, only to get
the same thing. With 2.4, I get to a command line but am still not
getting any video.

lspci: 
000:00:02.0 VGA compatible controller: Intel Corp. 82915G Express
Chipset Family Graphics Controller (rev 04)

In addition, the on-board IDE/RAID controller (which I want for normal
IDE only) doesn't seem to be supported. Which means I can't boot to a
KNOPPIX CD to check out what it's doing in X, since it can't find the
CD.

I can rip this apart and move the CD to IDE0:1, but this issue will
still persist either way, and I'll need support for more than two
drives. (This board only has one ATA100 IDE controller. The other two
are the VIA ATA133 slots.)

lspci:
000:02:04.0 RAID bus controller: VIA Tech. VT6410 ATA133 RAID
Controller (rev 06)

Silly me for assuming this would just work...