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From: gaynor@magnus.ircc.ohio-state.edu (Jim Gaynor)
Subject: Re: What are the possible memory configurations of an SE/30?
Message-ID: <1991Apr23.181407.23784@magnus.acs.ohio-state.edu>
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References: <1991Apr23.155150.7671@cec1.wustl.edu>
Date: Tue, 23 Apr 1991 18:14:07 GMT
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In article <1991Apr23.155150.7671@cec1.wustl.edu> bst2948@cec2.wustl.edu (Bryan Sauhsung Tung) writes:
>	I've already asked this question about the IIsi, but it seems
>that the SE/30 may be a better deal.  How many memory slots does the
>SE/30 have, and what size memory will the slots take?  Also, do all
>the slots need the same size memory?  Lastly, is upgrading memory in
>an SE/30 easy to do?

The SE/30 has 2 bank of 4 slots each.  Each bank must be filled with
SIMMs of the same size, and the really ought to be of the same speed
as well.  The SE/30 requires a minimum memory speed of 120ns, which
isn't difficult - most SIMM suppliers sell SIMMs that run at 70-80ns.

Thus, with 256k SIMMs, 1MB SIMMs, and 4MB SIMMs, you have the
following possible combos:

Total RAM	Bank "A"		Bank "B"
---------	--------		--------
1 MB		4 256k SIMMs		-empty-
2 MB		4 256k SIMMs		4 256k SIMMs
4 MB		4 1MB SIMMs		-empty-
5 MB		4 1MB SIMMs		4 256k SIMMs
8 MB		4 1MB SIMMs		4 1MB SIMMs
16 MB *		4 4MB SIMMs		-empty-

Once you start getting into the 4MB SIMMs, however, you run into the
memory limits that are introduced by the lack of a 32-Bit Clean ROM
for the SE/30.  From what I currently understand, you cannot address
more than 16MB of memory space on an SE/30 (or IIcs, or IIx...).  This
includes addressing space used by virtual memory, RAM, System ROMs,
and expansion card.  The sum may not exceed 16 MB.
-- 
 Jim Gaynor - Systems Analyst 1      + "Pooh hasn't much Brain, but he never
 Ohio State University ACS-FMS-OCES  |  comes to any harm.  He does silly
 gaynor@magnus.acs.ohio-state.edu    |  things and they come out right."
 gaynor@agvax2.ag.ohio-state.edu     +        -Piglet, from "Winnie-The-Pooh"
