Trying to to install NetBSD on a PowerTower Pro 200:

OpenFirmware 1.0.5
64 MB RAM, 2 GB Seagate
IMS TwinTurbo 128 video in bottom PCI slot
AsanteFAST 10/100 PCI

Apple Multiple Scan 20 display and
Apple Performa Display (fixed 640x480)

Install sets are on my Mac SE/30 (NetBSD 1.3, uptime 474 days :)
and I plan to install via FTP.

I used System Disk w/ OF 1.0.5 patches to set OF environment:

output-device   /bandit@F4000000/IMS,tt128mb8@F

With either display, I get a black-and-white `checkerboard'
pattern (or occasionally black-and-white stripes). In the
white areas, I can read the OF prompts.

Good news: I can boot the install kernel from floppy, and
run sysinst, but I don't want to proceed unless I can get
the display problem solved (this will be a workstation - serial
console won't do).

Any ideas?

~mark