🚀 go-pugleaf

In article <1992Aug31.211644.27931@u.washington.edu> djo7613@hardy.u.washington.edu (Dick O'Connor) writes:
>I wanted to add 4 MB of memory to a Z386/33 EISA machine, so I bought a
>4MB SIMM (ZA3800MK) from LA Trade and it worked.  I wanted to add 4 MB
>of memory to a Z386/25, so I bought the same piece and it worked.  Great!
>
>Now I want to add 4 MB to a Z386/25 that came from a Z286 with the Hug 
>386/25 motherboard upgrade added.  But that same piece isn't recognized 
>by this machine.  In fact, we upgraded two machines in this way, and
>neither of two distinct pieces (SIMMs) are recognized by either machine.
>
>I smell an incompatibility problem.  Or a jumper I don't know about?  The
>hardware manual included with the upgrade just says to put either 1MB or
>4MB SIMMs in the first open slot.  No help there.  Has anyone figured out
>how to do this properly or have any further info that might help?
>
>"Moby" Dick O'Connor                         djo7613@u.washington.edu 
>Washington Department of Fisheries           *I brake for salmonids* 
>-- 


Do you already have 4MB of 1MB SIMMs installed on this motherboard?
On early Z386/25s you must install a 1 MB SIMM in the first SIMM socket
as 4MB SIMMs don't work there.  Then, since 4MB parts must be addressed
on 4Meg boundaries, you must fill out the bottom 4MB of memory space with
1MB parts.

Pat


-- 
        Pat Crean               Zenith Data Systems
        Systems Engineer 
        crean%zds-oem@caspian.cs.andrews.edu