OK, let me see if I've got this right.  There are two motherboard revisions:
Rev 1	OF 2.0f1	Rage II+
Rev 2	OF 2.4		Rage Pro

The ROM is located between the Personality card and the SDRAM banks.
There are three ROM revisions:
Rev A	$77D.40F2	1997
Rev B	?
Rev C	$77D.45F1	1998

Any ROM will boot either motherboard, but some functionality may be missing.

The OF version reported depends on the motherboard, not the ROM.

Rev A ROM shipped with Rev 1 motherboard, Rev B ROM shipped with Rev 2
motherboard.  Was Rev C shipped with later Rev 2 motherboards, or only
after they stopped shipping Beige G3s?

Rev A	supports only Rage II+, only master IDE drives,
	OF supports floppy, long TFTP timeouts for netboot (up to 15 minutes!)
	MUST run System Disk to use IDE or SCSI drives

Rev B	supports only Rage Pro, master and slave IDE drives,
	OF doesn't support floppy,
	MUST run System Disk to use IDE or SCSI drives

Rev C	supports both Rage II+ and Pro, master and slave IDE drives,
	OF floppy support unknown, auto-detects and uses PCI video cards,
	"fixes" problems with G3 ZIF upgrades,
	Running System Disk seems to cause problems


Have I got it right?  What's the ROM version of Rev B?  Is there any way to
tell which version ROM is present *without* the use of Apple System
Profiler (which requires MacOS) or by turning it on and testing to see
which devices work properly?  That is, are there any physical differences
(labels) or OF commands that will tell them apart?

Thanks,
  -- MW

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