Image Map Image Map
Results 1 to 10 of 10

Thread: CMOS battery replacement for Compaq Prolinea 4/50

  1. #1

    Default CMOS battery replacement for Compaq Prolinea 4/50

    There is a jumper for an external battery... I've removed the yucky barrel battery (see picture) and I want to replace it the best way possible. Is the replacement battery rechargable? I can't find a manual anywhere online...

    Thank you,
    Roger

    20180908_171541.jpg
    Always interested in Atari 8-bit and 486/early Pentium era software & hardware!

  2. #2

    Default

    If you use the external option it probably isn't rechargeable. But don't worry about it either as those 3 or 4 AA alkaline cells will probably last 5 - 10 years anyway.
    ☀☀☀ Visit Take Another Step for both computer and non-computer related discussions. ☀☀☀

    If you're looking for DS/DD or DS/HD 3" or 5" floppy disks, PM me. I've got some new, used, and factory over-labeled disks for sale.

    There is a crack in everything. That's how the light gets in. -- Leonard Cohen

  3. #3
    Join Date
    Apr 2015
    Location
    Austin, Texas
    Posts
    1,229

    Default

    If you want to check if the external battery is rechargeable, poke a meter across the external battery header pins and turn the machine on. If you get voltage, you'll have to either use NiCD or NiMH battery replacements or put a diode in series with non-rechargeable batteries.

  4. #4

    Default

    On a side note, I got these error messages on boot up. I know the one refers to the CMOS battery. The other one refers to a keyboard error... I've tried multiple "known good" keyboards with the same results. The battery was right next to the keyboard connection on the MB. I removed the battery and didn't see a lot of corrosion on the MB (I gently brushed the affected area). I thought I'd try using my serial-PS2 adapter if the keyboard connection was toast but the computer doesn't recognize the keyboard in the serial port... any suggestions? I can't go any further in the boot process without hitting either F1 or F10 (as shown in the picture below). When I press any key on the keyboard, it beeps but nothing shows up on the screen...

    Thank you

    20180909_070322.jpg20180909_070337.jpg
    Always interested in Atari 8-bit and 486/early Pentium era software & hardware!

  5. #5

    Default

    There's always the chance of interior board corrosion that can't be seen or corrected.
    ☀☀☀ Visit Take Another Step for both computer and non-computer related discussions. ☀☀☀

    If you're looking for DS/DD or DS/HD 3" or 5" floppy disks, PM me. I've got some new, used, and factory over-labeled disks for sale.

    There is a crack in everything. That's how the light gets in. -- Leonard Cohen

  6. #6

    Default

    So basically, the MB is toast?!? That sucks...
    Always interested in Atari 8-bit and 486/early Pentium era software & hardware!

  7. #7

    Default

    Maybe Glitch can offer some input as he's repaired many boards that have suffered from battery corrosion. It would be of interest to hear whether or not he's successfully dealt with internal layer repair problems and, if so, how he's been able to correct them.
    ☀☀☀ Visit Take Another Step for both computer and non-computer related discussions. ☀☀☀

    If you're looking for DS/DD or DS/HD 3" or 5" floppy disks, PM me. I've got some new, used, and factory over-labeled disks for sale.

    There is a crack in everything. That's how the light gets in. -- Leonard Cohen

  8. #8

    Default

    Quote Originally Posted by dafivehole View Post
    I've tried multiple "known good" keyboards with the same results.
    FWIW, older Compaq's can be quite picky about keyboards. If you haven't tried the one that came with the unit, try and locate one. I've seen this on 386/486 Compaq's and that can be a real pain if you don't have an original to go with it...

  9. #9
    Join Date
    Apr 2015
    Location
    Austin, Texas
    Posts
    1,229

    Default

    Quote Originally Posted by dafivehole View Post
    I removed the battery and didn't see a lot of corrosion on the MB (I gently brushed the affected area).
    You must neutralize the battery goo, brushing what you see off doesn't stop the corrosion process. Remove the board and pour distilled vinegar over the affected area and look for bubbling/fizzing, which is a sign that battery goo is present. Once the bubbling stops, rinse the area with isopropyl alcohol to get rid of the vinegar.

  10. #10
    Join Date
    Sep 2016
    Location
    Shrewsbury, MA
    Posts
    301

    Default

    I've had similar keyboard trouble with a 486 Compaq I had. I managed to find one that worked with it but I couldn't get into the bios without the factory Compaq keyboard

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
  •