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Re: $1225 for an Apple IIGS???



Herbert Fung wrote:

The difference between a ROM 00/01 motherboard and a ROM 3 are pretty easy
to spot.

The ROM 00/01 motherboard only has one ROM chip and is located directly
beside the CPU. The onboard battery is soldered to the motherboard located
on the left edge of the motherboad.

The ROM 3 motherboard has two ROM chips beside the CPU, and also has 8 RAM
chips behind the ROM chips. The onboard battery is in a case next to slot 1.

Now in that nutty auction the motherboard looks like a ROM 3 to me. The only
difference is that the RAM chips are in sockets instead of soldered on the
MB, and the ROM chips appear to be EPROMs instesd.


Any ROM 3 can use EPROMs. To use EPROMs they installed longer sockets.
If you check any ROM 3 that uses the usual 28 pin ROMs you'll see that
the motherboard is made to use either 28 or 32 pin sockets.
I have some ROM 3s where one or the other ROM is an EPROM, some
where none are and some where both are EPROMs.
I always understood it was done that way so EPROMs could be used in
case Apple ran short of regular ROMs but I can't substantiate that.

	Wayne