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IBM Personal System 2 8550 50Z Processor upgrade

Posted: Wed Apr 05, 2017 12:58 am
by ThinkPad560X
I have a nice condition almost looks new IBM Personal System 2 8550 50Z and the white casing is still white and not yellowing. It didn't come with a HDD when I bought it way back and bought the largest that it would handle, a 120MB ESDI HDD.

I wanted to install Windows 95 at the highest on this machine but the floppy boots and says "This version of Windows requires a 386 processor" This desktop is a 286 Processor. I even tried Windows 3.1 floppies and just boots to a blinking post. So no OS on the machine. Is their a way to upgrade the processor chip to a 386 or even a 486?

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Wed Apr 05, 2017 1:33 am
by axur-delmeria
I found this page: http://john.ccac.rwth-aachen.de:8000/alf/ps2_50z/

There's a picture of an IBM SLC/50 upgrade board here:

Image

But it necessitates modification, as this part mentions:
This machine doesn't have the original 286 CPU. I upgraded it with an SLC/50 CPU module made by Kingston that gives a nice performance boost and allows to run 32-bit software. Originally, this module was made for 286 machines with a PGA socket for the CPU. IBM however switched to the cheaper PLCC case with the 50Z, so I had to unsolder the CPU socket and replace it with a PGA type. One could still put the 286 back in place because it is possible to put a PLCC socket on top of a PGA socket. The module itself offers a slot for a 387SX coprocessor; you cannot keep a 287 coprocessor when upgrading. That's not as bad as it sounds since a FP emulation on a 50MHz CPU is almost as fast as an old 287.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Wed Apr 05, 2017 2:00 am
by ThinkPad560X
I found some of these boards and even a brand new Kingston upgrade kit for IBM Model 50Z for $99
http://www.ebay.com/itm/KINGSTON-SX-20- ... SwWxNYwH8X

and a few more of these boards but they are out of my price range of upgrading this computer for its age.
They are too much money.

http://www.ebay.com/itm/KINGSTON-KTM-SX ... Swd0BV03RY

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Wed Apr 05, 2017 2:16 am
by ThinkPad560X
I don't know if the processor has pins on it or not, but the 386 processors them selves are cheap.

Here is what it has. "bottom page"

http://patcomps.weebly.com/

I'm guessing the 10 at the end means it has a 10Mhz processor.

The Processor chart. The socket has a PLC and the 386 has a PGA
(Copy Paste entire link)

http://www.cpu-world.com/Compare/964/In ... 6-16).html

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Wed Apr 05, 2017 3:27 am
by axur-delmeria
You cannot plug in a 386DX processor into a 286 board. Besides the socket difference, the 386DX uses a 32-bit data bus, while the 286 is 16-bit only.

The 386SX works because it has a 16-bit bus like the 286, but the two are not pin-compatible so upgrade boards like the Kingston ones are needed.

The IBM SLC/50 works because it's also derived from the 386SX, albeit with a built-in 8KB L1 cache.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Thu Apr 06, 2017 12:26 am
by ThinkPad560X
After reading on that link you'll have to solder a PLCC socket onto it where the PGA socket is.
I was going to buy the new $99 board. I noticed that the board had pins under it and looked at a 286 online to see how mine looks without removing it since I don't have the removal tool.

The PGA socket is different. http://www.ebay.com/itm/INTEL-N80286-10 ... Sw~otWeidV

I thought it was going to be a plug n play removal of the 286 Processor and install the adapter board.
I don't think it would be worth the money and I really don't solder and my eyes are bad anymore, if anything motherboard wise I still install memory "RAM" or CPU swap upgrades.

So the next move for the computer is how can I install Windows 3.1? I put in disk 1 and it just boots to a beeping prompt

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Thu Apr 06, 2017 5:32 am
by axur-delmeria
A deeper search leads to this: http://www.walshcomptech.com/ps2/kingston.htm#sxlcmd, which is apparently a Kingston 386SX upgrade module designed specifically for the 50Z, so no modding required.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Thu Apr 06, 2017 12:36 pm
by ThinkPad560X
So these will not fit mine as I have a SXxxLCMD Model. The SXNow LEM model is used on the 25-286 and 30-286 systems. It is designed exclusively for those systems, and will not fit correctly in the 50Z

http://www.ebay.com/itm/KINGSTON-SX-20- ... SwWxNYwH8X

http://www.ebay.com/itm/KINGSTON-KTM-SX ... Swd0BV03RY

These are the only ones I could find on ebay.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Thu Apr 06, 2017 1:12 pm
by ThinkPad560X
I bought the $99 brand new item. The seller said it should work and fit.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Fri Apr 07, 2017 11:37 am
by micrex22
ThinkPad560X wrote:I bought the $99 brand new item. The seller said it should work and fit.
It should if it's explicitly designed for the 50Z.

I have a 286-to-486 adapter running on my PS/2 30-286 motherboard.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Fri Apr 07, 2017 11:40 pm
by ThinkPad560X
It says for IBM 50Z models on the Kingston card.

I went and got a White IBM 15" LCD monitor to fit well with the IBM 8550 50Z desktop. It will also fit well with my IBM Aptiva and IBM Personal Computer 300GL. I already have 2 IBM CRT monitors. 1 basic tube and 1 true flat tube. Another would be a lot of room to take up.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Fri Apr 07, 2017 11:46 pm
by axur-delmeria
Report to us once you receive it. I'd like to know how much of a performance increase these little boards can give. :D

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Fri Apr 07, 2017 11:54 pm
by ThinkPad560X
Image of the desktop with monitor. http://patcomps.weebly.com/

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Sat Apr 08, 2017 12:20 am
by axur-delmeria
The screen matches well with the desktop even with a 15-year (or so) gap between the two, thanks to IBM's approach to aesthetics.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Sat Apr 08, 2017 1:13 am
by ThinkPad560X
I am going to be checking all my PCs CPU specs Name and its code name and need a simple plug and play software that can run on Windows 95-10. What is the easy to use CPU checker software?

I got CPU-Z and it works out fine for me.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Sat Apr 08, 2017 1:34 am
by axur-delmeria
Did you use the separate win98 version from the official site? I have no computer with win95 to confirm if it works.

Re: IBM Personal System 2 8550 50Z Processor upgrade

Posted: Sat Apr 08, 2017 2:38 am
by ThinkPad560X
I only did on Windows 2000 Pro so far. Trying to update Windows 98 but its not working anymore.