Welcome and have a nice time on board 😀

I have a mid range model PS/1, a 486 SX 25.
Yours might be a factory upgraded model, although these were not commonly upped to DX2 level (you'd want to use at least a heatsink with that processor)

those SIPP-like video RAM modules cost a fortune IF you can find them 🙁

A collection of drivers, see the bottom of the page for the 50 MB archive:

http://www.walshcomptech.com/selectpccbbs/

I have a 2133 as well.

Jolaes76 wrote:

A collection of drivers, see the bottom of the page for the 50 MB archive:

http://www.walshcomptech.com/selectpccbbs/

Awesome...Thanks for the link! I have a couple ps/2 systems myself that I need drivers for.

Jolaes76 wrote:

Welcome and have a nice time on board :) […]
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Welcome and have a nice time on board 😀

I have a mid range model PS/1, a 486 SX 25.
Yours might be a factory upgraded model, although these were not commonly upped to DX2 level (you'd want to use at least a heatsink with that processor)

those SIPP-like video RAM modules cost a fortune IF you can find them 🙁

A collection of drivers, see the bottom of the page for the 50 MB archive:

http://www.walshcomptech.com/selectpccbbs/

Thanks Jolaes76 😀 You wouldn't happen to have the original disks / images that it came with? I guess they should also work on mine. About the VideoRAM modules I guess I'll give it a search and see what comes up. I'll also look for the cache chips too.

Unfortunately, I don't have the original disks for my PS/1. I have not found other PS/1 floppy images yet. The basic stuff at the end of the page I linked in should get you started, though.

I have a mid range model PS/1, a 486 SX 25. Yours might be a factory upgraded model, although these were not commonly upped to DX2 level (you'd want to use at least a heatsink with that processor)??

Well what I find strange is that everything on it points to be a 486sx 25. Model number, name on the plastic cover...

Must have been an aftermarket upgrade. I have a 2133 Consultant with 486SX soldered in the MOBO with an 486 overdrive chip. 🤣

Nice find, Not bad for a days work

Hi all, finally after this much time I managed to have some time to work on it again and here's my new findings:

- The motherboard is without a doubt this one: http://ps-2.kev009.com/eprmhtml/eprm/f281.htm
- There's no hdd image of the original software anywhere on the internet 🙁
- The original specs of my machine were: 486 sx25 / 4MB / 170MB HDD
- Here's a copy of the german autoexec.bat / config.sys original files: http://ps-2.kev009.com/eprmhtml/eprmx/h12210.htm

I've asked a friend of mine which is a designer to redo the back sticker on the case and mine was pretty degraded.
I've also dismantled it (and lost a couple of black screws in the process (stupid me), and I'm preparing to take care of some rust that got into it. Luckily the motherboard escaped 😀

xeon3d wrote:

Well what I find strange is that everything on it points to be a 486sx 25. Model number, name on the plastic cover...

Quite possible a board from a different machine got transplanted into it.
.

Jolaes76 wrote:

those SIPP-like video RAM modules cost a fortune IF you can find them 🙁

I have manufactured my own 30-pin SIPPs simply by soldering pins onto 30-pin SIMMs. It worked out well.
You do have to make sure it's the right kind of RAM and if it doesn't use 30-pin SIPPs then I don't have a solution.

For this expansion module, I am pretty sure one would need the a service level manual (for the correct pinout). The chips themselves, however, are standard DRAM just like those already surface-mounted on the motherboard. Theoretically, it is not an impossible task.

Jolaes76 wrote:

For this expansion module, I am pretty sure one would need the a service level manual (for the correct pinout). The chips themselves, however, are standard DRAM just like those already surface-mounted on the motherboard. Theoretically, it is not an impossible task.

I didn't need a tech reference because I had correct SIPPs to look at in the first socket. Made it easy.
.
I've seen different info for the video RAM for different revs of this board.
Some said 20-pin SIPP, some said 30-pin SIPP, some said 40-pin ZIP.
.

Found the service manual for my machine here: http://ps-2.kev009.com/pccbbs/aptiva/63g2028.pdf . The board is a 2133A (not a normal 2133).

Now it seems I need to find some cache chips for it. According to the service manual they should be:

"If you are installing cache memory in a board with no cache memory previously
installed, install 128K or 256K as follows:
Bank 1 Add eight 28-pin modules: 32K × 8, 25 ns SRAM"

Anyone knows where I can source them?

xeon3d wrote:

Found the service manual for my machine here: http://ps-2.kev009.com/pccbbs/aptiva/63g2028.pdf . The board is a 2133A (not a nor […]
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Found the service manual for my machine here: http://ps-2.kev009.com/pccbbs/aptiva/63g2028.pdf . The board is a 2133A (not a normal 2133).

Now it seems I need to find some cache chips for it. According to the service manual they should be:

"If you are installing cache memory in a board with no cache memory previously
installed, install 128K or 256K as follows:
Bank 1 Add eight 28-pin modules: 32K × 8, 25 ns SRAM"

Anyone knows where I can source them?

Scavenge from other boards.
eBay
Electronics shops.
www.mouser.com/ProductDetail/IDT/71256S ... VQkCOw0%3d
www.mouser.com/ProductDetail/IDT/71256S ... 52b%2fE%3d
.
There are also Digikey and Farnell (aka: Element 14)
I dunno which is best where you are.
.

Thanks for the links. Sadly I don't have any other boards that are worth scavenging.

According to this: http://ps-2.kev009.com/eprmhtml/eprm/f281.htm, U38 Cache Memory Tag Socket (128KB/256KB) is a socket equal to the cache ones, but it's marked as Tag Socket? I have no idea on what to put there.... 🙁

Also, does vogons have a marketplace?

Nope, no sales or trading allowed here.
Anyway, that socket is probably for the tag RAM... Think of it as an index for the actual cache RAM. It should also be an SRAM IC, just like the rest of the cache. I don't know the capacity it needs for the 256KB of cache you want to put it, but another 32KB IC might do the job. Read the service manual throughly, as it should say how much tag RAM you should use.

xeon3d wrote:

Tag Socket? I have no idea on what to put there.... 🙁

It's in your manual pages 188 & 189.

manual wrote:

1055—Cache Memory […]
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1055—Cache Memory

Warning:
Memory cards are sensitive to static discharge. See “Handling ESD-Sensitive Parts” on page 4-47.
Cover (2005)
Adapter Card(s) (2035) if applicable
Riser Card (2045) if applicable.

Note:
Run the Configuration Utility after adding or removing memory.

If the system board has cache memory modules already installed, the computer has 128K of cache memory.
Upgrade to 256K by adding memory modules as follows:
Bank 2
Add four 28-pin modules: 32K×8, 25 ns SRAM.
Tag
Replace existing module with one 28-pin module: 32K×8, 20 ns SRAM.

If you are installing cache memory in a board with no cache memory previously installed, install 128K or 256K as follows:
Bank 1
Add four 28-pin modules: 32K×8, 25 ns SRAM (for 128K or 256K).
Bank 2
Add four 28-pin modules: 32Kx8, 25 ns SRAM (for 256K).
Tag
Add one 28-pin module: 32K×8, 20 ns SRAM (for 256K)
or 8K×8, 20 ns SRAM (for 128K)

So for 256k you need
- 8pc 32K×8, 25 ns
- 1pc 32K×8, 20 ns (for the Tag)
.