Image Map Image Map
Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: My PS/2 Model 25-286 is actually a 486? What?

  1. #1

    Default My PS/2 Model 25-286 is actually a 486? What?

    So first off, sorry if this particular machine doesn't belong in this section, but I really didn't know how to classify this machine in it's current state

    So, right to it then...

    8xet6fsf0qa41.jpg

    As you might be able to see, that isn't the machine's original system board, it's a reply board with a socketed Intel 486 DX4, two 72-Pin SIMM slots and an on-board IDE and SCSI(?) controller. This also isn't some hack-job by someone wanting to make their 25-286 a 486 at any cost, it's actually a board that was purpose built to go into this system as it utilizes all of the systems original connectors, riser and even the proprietary IBM floppy, so obviously Reply manufactured and sold this as an upgrade at some point. Unfortunately, my scouring of the Internet hasn't turned up much on this machine, though the markings on the board identify this as a "Reply 050087 02 Rev. A2"

    Anyways, this is one cool little board though I am wondering, does this take Industry Standard SIMMs? Or the proprietary, unobtainable IBM ones?
    Last edited by ButINeededThatName; January 14th, 2020 at 01:55 AM.

  2. #2
    Join Date
    Apr 2015
    Location
    Austin, Texas
    Posts
    1,860

    Default

    If the machine doesn't have IBM branded SIMMs, they're probably normal types.

    http://john.ccac.rwth-aachen.de:8000/misc/ps2cache/

    You can try some different SIMMs, the worst that will happen is the machine won't boot. It's not like IBM did something really dumb like swap VCC and GND pins around.

  3. #3

  4. #4

    Default

    What a find! Always wanted one of those.
    Compaq - “It simply works better”

  5. #5

    Default

    "Reply" PS/2s are the PS/2 Holy Grail.
    PS/2s--M-30,M-40SX,M-50Z, M-57, M-70, M-77, M-80

  6. #6

    Default

    what a find to stumble into

  7. #7

    Default

    Quote Originally Posted by Hal9000 View Post
    "Reply" PS/2s are the PS/2 Holy Grail.
    Definitely. Wish I could find the Reply board for the Model 80!
    Compaq - “It simply works better”

  8. #8
    Join Date
    Feb 2017
    Location
    Guildford, U.K.
    Posts
    338

    Default

    Louis's site is our current actively managed repository of all matters PS/2-related:
    http://ps-2.kev009.com/ohlandl/

    Scroll down until you find the Reply section.

  9. #9

    Default

    Quote Originally Posted by GiGaBiTe View Post
    If the machine doesn't have IBM branded SIMMs, they're probably normal types.

    http://john.ccac.rwth-aachen.de:8000/misc/ps2cache/

    You can try some different SIMMs, the worst that will happen is the machine won't boot. It's not like IBM did something really dumb like swap VCC and GND pins around.
    They are in fact industry standard (thank god). It had a single 16Mb stick shoved in it.


    Ah-ha! Thank you!


    Quote Originally Posted by Hal9000 View Post
    "Reply" PS/2s are the PS/2 Holy Grail.
    Quote Originally Posted by compaqportableplus View Post
    Definitely. Wish I could find the Reply board for the Model 80!
    Dang, I had no idea these were that rare.

  10. #10

    Default

    By the way, does anyone know what the cable I need to stick the original ESDI drive back in this machine looks like? I refuse to use a common lemming IDE drive with my exceptional PS/2 system

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •