IIgs ROM 00 to ROM 01 Upgrade Adapter

The IIgs ROM1 Adapter converts a ROM0 IIgs to a ROM1 by replacing the ROM on the motherboard. It allows an older Apple IIgs system to run newer software like GS/OS.

It’s user installable, and removable in case the IIgs needs to be downgraded. And unlike other solutions, this one does not block Slot 3 when using a ZIP-GSX or TransWarp GS and does not “stretch” or damage your motherboard socket so the original ROM can be replaced without issue.

Read more about the IIgs ROM1 Adapter on our Wiki.

Reviews, Install Guide, and Support are there also.