On Monday, April 2, 2012 12:08:09 AM UTC-4, Scott Holder wrote:

 The 68020 and 68030 aren't pin-compatible as far as I know, so if 
> someone's swapped them, it's not likely to work.
>

That was my impression as well.
 

> From a quick look at some old MacWorlds and books the Googles turned up, I 
> found the following table:
>
> *Manufacturer/accelerator** Logic board** CPU speed* *List price (1991)*
>
> Dove Marathon 020 SE 16 699
>
> Dove Marathon 030 Plus, SE, Mac II 16 699
>
> Dove Marathon 030 SE, SE 30, Mac II, IIx 32 1599
>
> So, there was a 68020 upgrade for SE, as well as an '030 upgrade 
> apparently. The one marked "030x" specifically seemed to be for the Mac 
> IIx, with a faster 68030. I wonder if they went the route some other 
> companies did (Daystar? Can't remember) and made one base accelerator with 
> various adapters for different Macs.
>

Which makes the presence of the 68020 even stranger.
 

> At any rate, it's a vaguely puzzling situation. Some pictures or scans of 
> the board might be interesting to see. I wonder if at some point in its 
> life, someone harvested the '030 for something and stuck a spare '020 on it 
> to avoid losing it or something. 
>

I thought the 68030 had a larger form-factor and more pins, but I cannot 
recall ever putting the two side-by-side, so that may be wrong.  I'll take 
a picture of this board.

It's hard to understand how an accelerator with no on-board cache would 
work.  Besides the CPU, there's a single PLD and two 74LS glue parts - 
nothing else.  It may simply have been a quick and dirty way to run a 68030 
in an SE at the original speed?

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