Rare Mac II?

[flyingtoasteroven]

I heard a story recently about someone paying $200 for a Macintosh II motherboard. The idea was that it was some rare variant and not a prototype or something like that. I have never heard of anything like that, so I'm asking you guys.

Any info?

 

[porter]

I thought the only mod for a II was the addition of a memory controller in order to be able to use virtual memory, that was merely plugging the new chip in.

 

[Unknown_K]

There are accelerators that you can buy for a Mac II, can't think of any Mac II motherboards worth anywhere near $200 stock.

 

[Macbuk]

i bought (1 month ago) two fully functional macintosh II and IIx motherboards for 20 euro... two months ago i acquired a Micromac carrera 040 33 mhz bundled with IIx and IIcx adapters for 50 euro.

I've seen some auctions with IIx adapter (like the one i have) over 100$ (buy it now) but i guess their price overinflated ...pure speculation.

http://img161.imageshack.us/img161/6656/micromac1zf8.jpg

do you know if IIx adapter like the one on the picture (top right corner) could be used to connect micromac carrera on a macintosh II?

does it need the original adapter that connects to the coprocessor slot too?

 

[Quadraman]

Some people charge ridiculous prices for Mac parts, and unfortunately some people pay it which makes it bad for the rest of us looking for parts as it drives the prices up. The only Mac II motherboard that I can think of that might be worth any sort of premium price would be a IIfx, but not $200.

 

[Charlieman]

There were two model numbers for the Mac II logic board. The first had soldered on batteries, the second had battery enclosures. The enclosures were available as a separate part for retrofitting to the earlier board. Neither logic board is particularly unusual or valuable.

Further to this, there were two ROM versions, the later version being required for some NuBus cards. Additional to these ROM versions are the IIx ROMs to support the 1.4MB floppy drive.

 

[Charlieman]

do you know if IIx adapter like the one on the picture (top right corner) could be used to connect micromac carrera on a macintosh II? does it need the original adapter that connects to the coprocessor slot too?

You need a Mac II version of the breakout board that provides a IIci PDS slot. The 68020 and 68030 are not pin compatible, so a board from a IIx, IIcx or IIfx will not work.

 

[flyingtoasteroven]

This is exactly as I thought. I guess either the board in question was a rare prototype or some Corp. had given their agent $200 to spend. The whole story came from I guy I bought a IIsi board from + RAM for $10 shipped.

Incidentally I was going to a Mac II today for $15, But I just got a call saying it didn't work anymore. No chime, no sale.

 

[flyingtoasteroven]

Mabye I should have jumped anyway. It had a daystar accelerator in it. Could it just need a new battery?

 

[Charlieman]

Yes. Flat batteries.

 

[Temetka]

Jump.

Now.

 

[Unknown_K]

Either way the accelerator is worth the price.

 

[trag]

Jump.
Now.

Yes, Kosh.

 

[IIsi]

You're talking about a II board with a MC68851 PMMU chip in em, since these are hard to find. I used to have one but sold it. The chip replaced the HMMU Hochsprung MMU chip that simply bridged 24 to 32 bitness. the PMMU allowed Virtual memory to be used, and contained a root table pointer to a tree of logical to physical address translations that were requested by the CPU, and a cache of some of these. if youre interested I might be able to track one down.

 

[IIsi]

I just realized who flyingtoasteroven is!! Haha, I'm slooow. You came to my house last weekend to get the 840AV. How's it doing by the way?