30gb disk hang in dkcsum(?)

[Ian Darwin <ian@darwinsys.com>]

My home server's main SCSI disk died, and I'm trying to replace it with a
30GB WD 7200rpm HD. Motherboard is an ASUS; CPU a 400 Intel Celery.
Disk is brand new; I was able to fdisk a partition onto it using
OpenDOS 7, so I believe the hardware is OK.

Current config: wd0 is the new disk, wd1 an old bootable drive.
Trying new disk by itself gave essentially same results.
Disable pcibios0 does not help. Setting wd* flags to e.g., 0xfac
does not help.

Last line is mtrr: Pentium Pro MTRR support (if I interchange the
two WD drives, gets out line line more: 
	dkcsum: wd0 matched BIOS disk 80).

Since it hangs before even going single user, I can't get a full dmesg.
Here is what I believe to be the relevant parts.

pciide0 at pci0 dev 4 fn 1 "Intel 82371AB"...
	channel 0 wired for compatability channel 1 (the same)
atapiscsi 0 at pciide channel 0
scsibus0 at atapiscsi0: 2 targets
cd0 at atapiscsi target 1
wd0 at pciide0 channel 0 drive 0 <WDC WD300BB-00AUA1>
wd0: 16 sector PIO, LBA, 28629MB, 16383 cyl, 16 head, 63 sec, 58633344 sectors
pcide0: channel 0 interrupting at irq 14
wd0(pciide0:0:0) using PIO mode 4, [rest varies depending on flags set,
		either Ultra-DMA mode 2, or DMA mode 2)

machine diskinfo
hd0 80 unknown 1024 255 63 0 0xae9668ce
hd1 81 esdi 761 14 50 2 0xa4df86cc