G3 mainboard broken?

Discussion in 'Macintosh Computers' started by Robofunc, Nov 10, 2004.

  1. Robofunc macrumors member

    Joined:
    Nov 10, 2004
    Location:
    Tampa, FL
    #1
    Hi. Let me preface this by saying that I was a PC person who made 'the switch' about 7 months ago. I always used Macs at work, but I never worked on the hardware like with PCs.
    The problem: A 400MHz blue-and-white machine with 9.2.2 installed. I'm looking to upgrade it to Panther, but it needs fixing first.
    The thing is extremely unstable, if it even boots at all. Usually it freezes during boot, however. I ran Tech Tool hardware tests on it and it kept crashing when I tested the RAM. I then tested each stick of RAM individually and then paired them off. I tried different sticks in different sockets to try and isolate the bad one(s), but I had the same problem with every stick in every socket. This makes me think the mainboard is bad. I'd like to replace it and see if there is any improvement, but I've been having a hard time finding one.
    Am I way off on my prognosis? Any tips?
     
  2. Robofunc thread starter macrumors member

    Joined:
    Nov 10, 2004
    Location:
    Tampa, FL
    #2
    *Bump*

    Did I say something that made me sound too stupid for anyone to want to answer?
     
  3. cubist macrumors 68020

    Joined:
    Jul 4, 2002
    Location:
    Muncie, Indiana
    #3
    The problem is, we can't be sure that any of the RAM is the right RAM for this computer. Where did the RAM come from?

    Other questions: Has the machine been moved (transported) recently? If so, I'd check cable connections. If there are any PCI boards, make sure they're pressed down into their sockets well (they tend to wiggle out). Same thing for the CPU module (be very careful here).

    Hold down cmd-apple-P-R and reset the PRAM. There's also a little "cuda" button on the motherboard (help here, someone who's more familiar with the B&W).

    Blow out dust. Use a soft white pencil eraser to clean the RAM data edges (this is controversial). Make sure interior of machine is clean, dry and warm.

    B&W's are very reliable machines, real workhorses. With enough RAM in here, it'll run Panther quite well.
     
  4. Sun Baked macrumors G5

    Sun Baked

    Joined:
    May 19, 2002
    #4
    Plus that was a common problem with that old OS, the extension/control panel/files in the wrong folder/ect. conflicts would always cause problems and would take awhile to fine tune the machine to stability.

    So it's either HW or SW, it's hard to tell.
     
  5. mim macrumors 6502

    Joined:
    Apr 24, 2003
    Location:
    flesh, melbourne.... heart, london
    #5
    That's a really good point. It may be worthwhile to get hold of a Panther CD and see how it boots (ie - from the CD). If you get to the install utility then it's probably a problem with the extension on OS9 (I helped manage 60+ macs in the pre-OSX era, and I did not like them then at all). Before that though, try these:

    Try starting up OS9 with extensions disabled (hold down shift key during reboot-startup until you see the "extensions off" notice). If you boot fine, then it's an extension conflict. This is not so uncommon on an older machine that has probably had a lot of garbage installed on it over the years. There is an extensions manager which you can use to turn on extensions 1 by 1 to see where the problem is (this may take along time if there are loads of extensions!).

    Zapping the pram may help. If you can get it to boot, try rebuilding the desktop - cmd(that's Apple Key)+option after startup chime.

    I would think it's more likely to be a problem with the software than with the hardware. Those B&W's were pretty solid machines.

    [edit: I should also say that if you get the machine working ok, you should get Panther as soon as possible. OSX is a joy to use :) If you can afford it, you may want to upgrade your video card - get as much VRAM as possible - so that Quartz Extreme (the graphics subsystem) enables.]
     
  6. Robofunc thread starter macrumors member

    Joined:
    Nov 10, 2004
    Location:
    Tampa, FL
    #6
    Thanks for your replies.

    I got this machine as from my company when we moved to new offices, so it was moved recently, but the cable connections and PCI cards are all secure.

    I did try disabling the extensions and zapping the p-RAM first. The machine will still freze during boot, extensions off or not.

    9.2.2 is a fresh install, anyway, so I'm sure that the extensions and control panels are all in the right places.

    There are 640 megs of RAM in this machine, with two Edge PC-100 256 sticks ammending the original two sticks of 64 megs each. I tested the machine using the original RAM by itself, as well as the newer RAM, and got the same failed RAM test in Tech Tool.

    There was a previous problem with cross-threaded files destroying the system in this machine, but the hard drive was replaced with a new, clean one before 9.2.2 was installed. Could the cross-threading problem be caused by a bad peice of hardware (thus making causing it to reoccur), or is that kind of problem usually software derived? Tech Tool said my files and system were free of errors...

    This isn't my only machine. I have a dual 1gig g4 with 1gig RAM running 10.3.6 as my home machine, and a single 1.8 gig g5 at work, so I am aquainted with the joys of OSX. My plan was to get this machine running Panther, provided I can get it working correctly.
     
  7. mim macrumors 6502

    Joined:
    Apr 24, 2003
    Location:
    flesh, melbourne.... heart, london
    #7
    <snip>

    Sorry then Robofunc. It may well be some kind of hardware problem then (not necesarily the ram itself if you've tried swapping it all around). Sometimes if you boot into open firmware (cmd-option-o-f) it will notify you of a particular device that isn't responding.

    If you want to get hold of another motherboard you could try posting in the Macrumors marketplace forum http://forums.macrumors.com/forumdisplay.php?f=14.

    Good luck.
     
  8. Robofunc thread starter macrumors member

    Joined:
    Nov 10, 2004
    Location:
    Tampa, FL
    #8
    Argh. That's what I was afraid of. Thanks for helping clear things up.
     
  9. tucker macrumors newbie

    Joined:
    Jul 23, 2002
    Location:
    Mississauga, Ontario
    #9
    Broken G3

    There was a problem with early B&W G3's, Ram that would work in later up-dates would not work in the early versions( all were PC100's) if this machine was at work could the ram be from other machines????? you have to use spacific PC100 sticks.
     
  10. Robofunc thread starter macrumors member

    Joined:
    Nov 10, 2004
    Location:
    Tampa, FL
    #10
    Tucker—

    As far as I know two 64-meg sticks are what this machine shipped with. They have little stickers saying "warranty void if removed." This machine was originally in our NY office and was shipped here to FL after being well used, so it is entirely possible that none of the RAM is actually OEM to this particular machine.

    If this is the case, how do I go about getting RAM that will work?
     
  11. tucker macrumors newbie

    Joined:
    Jul 23, 2002
    Location:
    Mississauga, Ontario
    #11
    Re G3

    Other World Computing
    div. of New Concepts Development Corp.
    1004 Courtaulds Drive
    Woodstock, IL 60098
    815-338-8685

    carries it, make sure you tell them it is a B&W G3 and you are having trouble with Ram. I would take you G3 into a Mac dealer/apple store and have it tested first just in case it is the mother board not the ram that is the problem. I still use 9.2.2 on some of my machines and have very little trouble.
    Good luck
     

Share This Page