6.1.0 S error booting from HD

Can boot fine from installation floppy, but trying to boot without it I get:

Boot partition 1 ? 1
Hit Esc for .altboot…S_

blinking cursor, hangs there.

Hardware is a crusty old Neptune chipset Socket 5 Intel Pentium motherboard
extracted from a 1994 vintage Dell, WinChip 180, 16 MB RAM, 1.2 GB Western
Digital HD.

PS also had trouble with system thinking drive was >8 GB, got around that
per the KB, then this problem.

Thanks in advance -