[comp.sys.3b1] Memory

aegnor@bsu-cs.bsu.edu (David C. Powell) (03/22/91)

How much memory can you take the 3b1/7300 up to!?  I have a 512K motherboard,
one 2 meg board and added another IDENTICAL 2 meg board to the PC, BUT it
only recognizes 2.6Meg, can the unix pc NOT handle 4.5?  and if it can, why
would 2 of the same memory boards NOT work!?

I have just started getting into the 7300, like I have had it, but it has
been gathering dust for, oh 5 months, and now I am loading 3.51 on it (sigh
only the 20Meg hd at the moment) and would like to have MORE than 2.5Megs
in this thing....  I noticed in the EIA/RAM board manual (I have the manual
but NO board by the by, just memory on them thar boards, no RS232 ports)
that the biggest memory size it listed/gave a combination of memory boards
to reach that size was *4* Meg, is that the memory limit in the 3b1 or
do I have problem!?

E-Mail or post ANY and all info!!!!


Thanks!!!!


-dcp



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tkacik@kyzyl.mi.org (Tom Tkacik) (03/22/91)

In article <12548@bsu-cs.bsu.edu>, aegnor@bsu-cs.bsu.edu (David C. Powell) writes:
> How much memory can you take the 3b1/7300 up to!?  I have a 512K motherboard,
> one 2 meg board and added another IDENTICAL 2 meg board to the PC, BUT it
> only recognizes 2.6Meg, can the unix pc NOT handle 4.5?  and if it can, why
> would 2 of the same memory boards NOT work!?

Too much!  You have too much memory in your 3b1.  The 3b1 can have a
maximum of 4 Meg of memory.  But there is another limit that is also
biting you.  The 4 Meg HAS to be split 2Meg on the motherboard, and
2Meg on expansion boards.

You machine is only recognizing one 2Meg expansion board.  That plus the
.5Meg on the mother board gives you the 2.5Meg that you see.  You may as
well remove one memory board and give it to some needy person.
(I already have 4Meg in my machine, but thanks for the offer.:-)

The only way to get more memory now is to add more to the motherboard.
Rip out those small 64K RAM chips and populate it with 256K RAM.
This is not something for the weak of heart, or the inexperienced.
You will need a good soldering iron, solder sucker, and a whole lot of time.

Good luck!
-- 
Tom Tkacik                |
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