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SIMM memory: What is the maximum size?

Posted: Tue Jun 14, 2005 3:27 am
by fabiobol
I have just bought a lot of SIMM-MEMORIES, but, unfortunately, i have only 2 slots on my motherboard, and I couldn't go over 16 MB. I know that tis kind o f memory must be installed "in pairs", but, I would like to know the maximum size for a single-simm memory. Aren't there any 128 MB-SIMM?

Posted: Tue Jun 14, 2005 8:25 pm
by Wally
There most certainly is 32 MB simms. Why wouldnt there be?

EDIT After Identity Crisis Corrected me

Posted: Tue Jun 14, 2005 9:46 pm
by Identity Crisis
AFAIK, SIMMs only go up to 32 MB per stick.

Posted: Tue Jun 14, 2005 10:27 pm
by jmmijo
Now then, please make sure you clarify what type of SIMM slots these are, the older 30-pin kind which had to be installed in either matched pairs or matched quads, depending on the motherboard of course ;). Or the 72-pin variety, in which case these did indeed go up to both 64MB and 128MB capacities.

I recall that 30-pin SIMM modules only went up to 16MB in capacity, which were extremely expensive at the time.

Posted: Wed Jun 15, 2005 10:36 pm
by Unknown_K
Most older systems only like 32M 72pin simms or smaller (especialy 486 systems).

30 Pin memory came in 256K,1M,2M (rare),4M,8M (not too common) and 16M

Posted: Thu Jun 16, 2005 12:07 pm
by jmmijo
Yeah K, you're right, I kind of forgot about this, I guess it depends on the make/model machine and/or motherboard.

I wonder however if you can still find some firmware updates for these older machines ?!?

Guess that depends on how much Google finds for you ;)

Posted: Thu Jun 16, 2005 10:11 pm
by Unknown_K
Older machines had burned roms, not flashable firmware like in the later machines Pentium and later.

Posted: Thu Jun 16, 2005 10:16 pm
by jmmijo
Yeah I seem to recall that too, however I think Asus may have been one of the early adopters of EEPROM ;)

Posted: Tue Jul 12, 2005 5:13 pm
by kreats
Yup jmmijo is right, 30 pin simms go up to 16MB and 72 pin simms go up to 128MB

In the PC world, not many 486 motherboards supported 16MB 30 pin, and mainly Pentium Pro chipsets supported 64Mb+ simms of 72 Pin.

You'll find lots of non-pc related machines that support larger simms though (68k macintoshes, amigas, sun boxes, etc). 16Mb 30 pin is popular for maxing out old macs like the SE/30 (which can take 128MB).

Posted: Tue Jul 12, 2005 11:39 pm
by Unknown_K
My Quadra 950 (Mac) takes 16x16mb 30 pin simms for 256MB total (I have 3 banks of 16mb and one of 4mb in it now)

Posted: Wed Jul 13, 2005 5:49 pm
by kreats
yep, so did mine until the power supply died! It is insanely heavy and impossible to find a replacement for it.. I considered doing an atx power supply mod, but I don't want a frankenmac.

I used to have the dream of building it up into an avid workstation.. but think I'll have to let that one go now sadly.

Posted: Wed Jul 13, 2005 5:54 pm
by Unknown_K
I have another 950 with a dead PS, still hoping to find a replacement for it.

Posted: Wed Jul 13, 2005 6:53 pm
by Wally
i got a quaDRA 900 with the same amount of ram