PS/2 Model 30-286

[IBMMuseum]

You mean these ram SIMMS?.

Those are one version of the much more common 256Kb IBM SIMMs...

 

[kishy]

If those are more common, we're all screwed. Those on their own are uncommon enough.

 

[Unknown_K]

I have a bunch of IBM RAM that uses those small memory "cans", I think they are for the PS/2 80 towers but they are not 30 pin SIMM. As far as I know only IBM used them and each of the 2 "SIMMs" is probably just 1-4MB (very tall).

 

[tezza]

If those are more common, we're all screwed. Those on their own are uncommon enough.

Yes, IBM PS/2s. While generally MS-DOS/Intel compatible as far as software goes, the hardware is full of proprietry stuff.

Tez

 

[Chromedome45]

My model 30-286 has two of those ugly metal can 256k SIMMS. But they do work :D. I am still awaiting my SIMMS i got off epay to get here. I am guessing today or tomorrow.

 

[IBMMuseum]

I have a bunch of IBM RAM that uses those small memory "cans", I think they are for the PS/2 80 towers but they are not 30 pin SIMM. As far as I know only IBM used them and each of the 2 "SIMMs" is probably just 1-4MB (very tall).

Yes, the proprietary Model 80 memory boards (http://ibmmuseum.com/ohlandl/8580/8580_Planar_Memory.html) uses the "sugarcube" chips only on the 1Mb module. These boards were designed from other equipment (there is a story there) and to use up the surplus chips. IBM made higher capacity modules of 2Mb and 4Mb (The Model 80 systems have three separate planars for the different CPU speeds of 16, 20, and 25MHz. Later 25MHz "Axx" planars cannot use the 1Mb boards. Conversely, the two lower speed planars cannot use the 4Mb boards) with regular memory chips on them. Kingston also produced an aftermarket 4Mb board for the Model 80 ("Axx" version) as well.

 

[Chromedome45]

Ok the IBM memory kit arrived today and it works...Sort of. Let me clear that up. If 256k simms in bank 0 (nearest to where power supply cables plug into motherboard) and 2mb kit in bank 1 I get 1mb memory weird huh. Ok now if I put 2mb kit in bank 0 and 256k simms in bank 1 I get 4mb memory weirder, I than get memory error 203 not suprising since it thinks the 256k simms are 1mg simms. So it seems as though the memory size is dictated by the size of the simm slots in bank 0. Very odd. So I have just the 2mg kit in bank 0 and nothing in bank 1. Total memory is as expected 2Mb.
Sorry long winded but needed to tell what was going on and hopefully will help others. The 1 Meg Simms part number is: 62X5723 as stamped on back of each chip 2 meg kit part number is: 30F5360.

 

[modem7]

Ok the IBM memory kit arrived today and it works...Sort of. Let me clear that up. If 256k simms in bank 0 (nearest to where power supply cables plug into motherboard) and 2mb kit in bank 1 I get 1mb memory weird huh. Ok now if I put 2mb kit in bank 0 and 256k simms in bank 1 I get 4mb memory weirder, I than get memory error 203 not suprising since it thinks the 256k simms are 1mg simms. So it seems as though the memory size is dictated by the size of the simm slots in bank 0. Very odd.

IBM information supplied in an earlier post includes "Different size SIPs cannot be used together on the system board." Therefore, what you are attempting is not valid.

 

[Chromedome45]

You sir are correct I missed that part. Thanks for pointing it out Modem7. Now it makes sense.

 

[MikeS]

Are you (or anybody) interested in a copy of the PS/2 Model 30 Guide to Operations?

About 60 pages; not much useful info, but nice to have. In slipcover, also 16 page brochure "IBM PS/2 Display Installation and Testing Instructions" (even less useful info) and copy of starter disk.

$5.00 + S.