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Shadow Lord
March 30th, 2012, 01:13 PM
Just saw this posted on eBay:

8359

I recognize the memory card but the SIMMs is what got me interested? Is that a special kind of memory or is it that square memory IBM was using for a while (monolithic memory I think it was called) or is it just white memory chips pictured weirdly?

Elvi
March 30th, 2012, 02:56 PM
I have 2 of those in my IBM 8530-021.
http://electricdreams.ath.cx/ram/256kb30pinsimm.jpg
Not exact match but similair.

IBMMuseum
March 30th, 2012, 08:20 PM
Just saw this posted on eBay:

8359

I recognize the memory card but the SIMMs is what got me interested? Is that a special kind of memory or is it that square memory IBM was using for a while (monolithic memory I think it was called) or is it just white memory chips pictured weirdly?

256Kb each SIMM, wired to IBM's own proprietary standard...

Shadow Lord
March 30th, 2012, 08:25 PM
256Kb each SIMM, wired to IBM's own proprietary standard...

Interesting so does that mean that regular SIMMs won't work in this card? I know on your site I saw a reference to this card as maybe having the same memory as an IBM caching SCSI controller...

IBMMuseum
March 30th, 2012, 09:30 PM
Interesting so does that mean that regular SIMMs won't work in this card? I know on your site I saw a reference to this card as maybe having the same memory as an IBM caching SCSI controller...

Regular (256Kb) SIMMs wouldn't work, unless they are rewired. As the IBM 1Mb modules that replaced their 256Kb SIMMs were hard to find, Alfred Arnold made a page (http://john.ccac.rwth-aachen.de:8000/misc/ps2cache/) about rewiring the more-common clone 1Mb SIMMs (we started calling them "Industry Standard" to distinguish them for IBM versions) primarily for the "Spock" SCSI controller. There were some of the early PS/2s and other IBM units that could also use the IBM 1Mb modules:

Model 25 286
Model 30 286
Model 50-021 (non-'Z', which was a single 72-pin SIMM)
Model 60

IBM Industrial "Gearbox 800" (which had a SCSI controller with "Spock" elements)

I tried to get 1Mb SIMMs I modified to work in a Model 30 286, but they would end up failing within a few days. None of the particular styles would last for me, although I should have tested them more on a "Spock", just to see if the planars were more sensitive. Who knows, time is the thing I lack now, not the SIMMs or systems.

The 256Kb IBM SIMMs can be found (the more modern variety has nine almost square black plastic chips), but I've only heard of the 512Kb modules in print...

Maverick1978
March 31st, 2012, 05:19 PM
I believe that they're commonly referred to as "sugar cube" modules... similar ones could be seen on the proprietary memory for the IBM PS/2 8580 tower system.

Unknown_K
March 31st, 2012, 05:38 PM
I tried to get 1Mb SIMMs I modified to work in a Model 30 286, but they would end up failing within a few days. None of the particular styles would last for me, although I should have tested them more on a "Spock", just to see if the planars were more sensitive. Who knows, time is the thing I lack now, not the SIMMs or systems.

How did they fail?

Shadow Lord
March 31st, 2012, 06:10 PM
How did they fail?

My question as well.

Thanks!

Shadow Lord
March 31st, 2012, 06:32 PM
Regular (256Kb) SIMMs wouldn't work, unless they are rewired. As the IBM 1Mb modules that replaced their 256Kb SIMMs were hard to find, Alfred Arnold made a page (http://john.ccac.rwth-aachen.de:8000/misc/ps2cache/) about rewiring the more-common clone 1Mb SIMMs (we started calling them "Industry Standard" to distinguish them for IBM versions) primarily for the "Spock" SCSI controller.

....

The 256Kb IBM SIMMs can be found (the more modern variety has nine almost square black plastic chips), but I've only heard of the 512Kb modules in print...


I believe that they're commonly referred to as "sugar cube" modules... similar ones could be seen on the proprietary memory for the IBM PS/2 8580 tower system.

Thanks for the info both of you. Very interesting. I was tempted to try the mods until I saw the soldering skills required. Definitely not for me!

Does anyone know where I can get some of the modules? 256K, 512K, or even 1MB? The card supposedly handles anywhere from 0.5MB to 6MB of memory.

twolazy
March 31st, 2012, 07:15 PM
Would simms from an 8560 work?

Shadow Lord
April 1st, 2012, 09:41 PM
Would simms from an 8560 work?

According to IBMMuseum's post - no. Those were probably "industry std." simms by then.