Anyone using an Intel AboveBoard MC on a Model 80?

jpero at jpero at
Thu Apr 10 12:14:36 CDT 2008

> Title says it all...  I picked up a "new" (still in shrink-wrap) 
> AboveBoard MC with the intent of using it in my PS/2 model 80 and I'm 
> having serious issues getting it to function properly.
> I've read that the Model 80 has trouble (not sure precisely /what/ 
> trouble) with more than 16mb of memory, but even limiting the AboveBoard 
> to 4mb is problematic.
> Anyone have any ideas?  Similar/different experiences?
> Thanks,
> Josh

1.  The card is 32 bit not 16 bit MCA?  Have to be 32 bits for 
stablity and speed in your 386 (model 80 are.), on this reason I went 
with 32 bit MCA memory card in my 70-Axx.  You need to get a memory 
card of 32bit MCA using 72 pin SIMMs.  This ram card model you got is 
specifically made for 8088 and 286 models.

2. The simms have to be 9 chips ONLY and speed 80ns or less for this 
aboveboard/MC.  Nothing else will work right on these models.  If you 
get 32bit MCA ram cards using 72 pin simms, if you got quality 
generic ones, modify them to IBM specs by arranging the presence 
sense lines via 0 ohm SMD resistors.  Info are out there on 'net.

3.  That card is good as expanded ram card in 386 machines.

4.  You are correct that these older machines have hard 16MB 
limitations due to DMA limited to 24bits I think (same as 286) that 
as far as I know.


Cheers, Wizard

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