Weird Apple IIgs with Multiple ROM Chips?

[Arcady]

Does anyone know why a IIgs would have a daughtercard in the ROM socket with 4 EPROM chips on it?

This is on what I believe is a prototype IIgs motherboard.

 

[HoJoPo]

They used an adapter with lower-capacity EPROMs during development, because they were cheaper. The production ROM 03 IIgs uses a PROM, cheaper to mass-produce, but can only be programmed once. Where the EPROMs on the adapter board can be re-written as they develop/test code.

 

[Arcady]

Okay. So this is definitely a prototype then. Any idea how many of these are out there, and if it is worth something to a collector? I've really only got an interest in standard issue computers, not one-of-a-kind stuff like this.

 

[dorkbert]

or could be a advanced seeding unit sent to software development houses. not terribly common.