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Mac II upgrade possibilities
Posted by: robin-fo on 2022-10-23 13:14:39 Hi everybody, Recently I received a working Macintosh II logic board which I‘d like to put into a battery bombed IIfx case. I already ordered a 68851 to replace the Hochsprung MMU to gain A/UX compatibility. Is there any chance to replace the ROM chips with IIx (or even Quadra) ROMs to gain FDHD support without losing early A/UX compatibility? Could I even replace the 68020 with a 68030 (I guess not)? Cheers, Robin
Posted by: Unknown_K on 2022-10-23 13:30:57 You need new ROMs and a replacement SWIM chip for superdrives. 68020 will not accept a 68030 (different socket).
Posted by: Phipli on 2022-10-23 14:41:20 Hi everybody, Recently I received a working Macintosh II logic board which I‘d like to put into a battery bombed IIfx case. I already ordered a 68851 to replace the Hochsprung MMU to gain A/UX compatibility. Is there any chance to replace the ROM chips with IIx (or even Quadra) ROMs to gain FDHD support without losing early A/UX compatibility? Could I even replace the 68020 with a 68030 (I guess not)? Cheers, Robin Dove made a processor upgrade that replaced the 020 with a 32MHz 030 in the socket. There were also Daystar adapters that let you plug in a PDS accelerator. Photos of the Dove device here : https://www.applefritter.com/content/dove-computer-marathon-030-mac-ii-accelerator-board Note that isn't the same as a Dove Marathon 030x/SE. Attached are benchmarks from an old magazine article... Macworld circa 1991?? Its just something I had saved.
Posted by: joshc on 2022-10-23 20:01:16 With a Daystar Macintosh II Adapter, you could fit a Daystar 68030 or 68040 (I think) upgrade to your Mac II. The tricky bit is finding those cards...I had them at one point, and I must say, a 50Mhz 68030 Mac II is a cool thing indeed.
Posted by: robin-fo on 2022-10-23 22:08:16 Thanks everybody, any suggestions about the choice of ROMs?
Posted by: Juror22 on 2022-10-23 22:48:53 The ROMs/SWIM are listed on p.197 of Macintosh II Repair and Upgrade Secrets.
Posted by: Juror22 on 2022-10-24 14:07:51 My Dove Marathon upgraded Mac II came along with this upgrade as well: So, don't forget to pick up one of those 🙂 They make popping out the batteries so much easier.
Posted by: joshc on 2022-10-24 17:07:05 My Dove Marathon upgraded Mac II came along with this upgrade as well: View attachment 47878 So, don't forget to pick up one of those 🙂 They make popping out the batteries so much easier. Yeah, that’s an actual Apple part that Apple would fit if you took your Mac II to a dealer to have its batteries replaced!
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