I got the case open today to see what's inside. It's the normal 8MHz 68000, with a 1MB RAM upgrade, and a Brainstorm card with 128K ROM and SCSI upgrade. The Brainstorm card fits right into the motherboard ROM sockets, and has two new ROM chips, as well as some stuff I assume is for SCSI, and a SCSI connector:
The RAM upgrade uses two stacked DRAM chips in each spot, with all the pins soldered together except one, which I'd guess is the chip select pin. It sits in some kind of motherboard overlay plate that lies on top of the motherboard. This plate also contains an additional chip next to the CPU, where I believe the normal Mac motherboard is empty. Probably a modified address decoder? Check out the stacked DRAMs:
Both the logic board and the analog board look pretty clean, and I don't see any evidence of capacitor failure. Is there any reason to monkey with replacing the capacitors? I'd rather not, if it's not necessary. A couple shots of the analog board:
Ideally I'd like to return this Mac to its original state as an unenhanced Mac 512K. I could probably make new ROMs with the 64K ROM image and put them in the ROM sockets, but I don't think I can undo that RAM upgrade. And I'm not sure what a 64K ROM would do if it found itself in a machine with 1MB of RAM.
The RAM upgrade uses two stacked DRAM chips in each spot, with all the pins soldered together except one, which I'd guess is the chip select pin. It sits in some kind of motherboard overlay plate that lies on top of the motherboard. This plate also contains an additional chip next to the CPU, where I believe the normal Mac motherboard is empty. Probably a modified address decoder? Check out the stacked DRAMs:
Both the logic board and the analog board look pretty clean, and I don't see any evidence of capacitor failure. Is there any reason to monkey with replacing the capacitors? I'd rather not, if it's not necessary. A couple shots of the analog board:
Ideally I'd like to return this Mac to its original state as an unenhanced Mac 512K. I could probably make new ROMs with the 64K ROM image and put them in the ROM sockets, but I don't think I can undo that RAM upgrade. And I'm not sure what a 64K ROM would do if it found itself in a machine with 1MB of RAM.