iMac G5 brought back to life

Discussion in 'PowerPC Macs' started by CooperBox, Feb 18, 2016.

  1. CooperBox macrumors 6502a

    CooperBox

    Joined:
    Nov 28, 2010
    Location:
    France - between Ricard & Absinthe
    #1
    A few months ago when visiting a local 'CashBack' store, I noticed that the guy responsible for the computer section was in a bit of a turmoil. I've got to know him pretty well, as every time I look in, I ask if he has any interesting Mac hardware (99% of the computers bought in, and then resold in the store are Win PC's).
    On this particular occasion he'd just prepared the sales card for a 17" iMac G5, and during a final test run, found that after booting to the desktop the machine then shut-down. Same after every attempt. He pulled the screen, and glared inside. He greeted me, and asked if I knew anything about that model. The logic board didn't look too clean, and with a closer inspection I immediately recognized the classic capacitor trauma - counting no fewer than 9 that were bulged and/or leaking. I pointed to them and told him, "That's the problem!"
    After uttering a mouthful of French expletives, he said his boss would go mad that he'd bought in material that was defective, that he didn't have the parts, and especially the time to perform any repairs on it.
    The next question surprised me. Did I want it, really cheap? The immediate answer was, no not really, as I'd never changed any capacitors, didn't have any spares, and had never even laid hands on an G5.
    Long story short. He pulled a PowerMac 'Digital Audio' G4 and 17" Apple Studio Display out from a store-room and asked if I would take them off his hands (plus the iMac) for a handful of dollars.
    Those sort of favours I don't mind, and arrived home with my 'pocket-money' purchases, and the sole preoccupation of where to store them so that the 'little lady' wouldn't immediately find out!

    Checking again inside (can't really believe I bought this, or where to start)......

    G5-inside1.jpg


    Defective capacitors marked up........----->

    G5-Capac2.jpg

    A fair amount of reading on this forum and elsewhere, indicated one could buy complete kits specifically for this repair. A kit was ordered and received, and I started to disassemble the G5.
    Ifixit was very useful, but I always make a habit of taking my own photos, which often show the detail of cable runs, Kapton tape locations etc, which is invaluable for rebuild reference purposes.
    Now I'm unsure if the previous owner was a purveyor of horse-hair or a barber, but whatever, the interior showed evidence of a hairy environment.
    Lower fan inlet location:

    Dust1.jpg Dust2.jpg

    I removed the logic board, and then located a very handy and willing guy with a soldering-station to change out all 25 capacitors: 20 were 1800uF 6.3V and 5 were 1000uF 16V.
    The guy had never worked on a G5 board before, and confirmed what I had read - that they were pretty difficult to remove. The next day I re-assembled the iMac, held my breath and pressed the power button.
    Bingo! Brought back to life.

    G5iMac-completed.jpg
     
  2. jbarley macrumors 68030

    jbarley

    Joined:
    Jul 1, 2006
    Location:
    Vancouver Island
  3. mark8 macrumors member

    mark8

    Joined:
    Nov 29, 2010
    Location:
    WNY
    #4
    I removed the logic board, and then located a very handy and willing guy with a soldering-station to change out all 25 capacitors: 20 were 1800uF 6.3V and 5 were 1000uF 16V.
    The guy had never worked on a G5 board before, and confirmed what I had read - that they were pretty difficult to remove. The next day I re-assembled the iMac, held my breath and pressed the power button.
    Bingo! Brought back to life.

    View attachment 617085 [/QUOTE]

    nicely done!
     
  4. Daniël Oosterhuis macrumors 6502a

    Daniël Oosterhuis

    Joined:
    Jan 10, 2016
    Location:
    Black Mesa Research Facility
    #5
    I need to find a local handy and willing guy to do my solder work. :p
    I do have a soldering iron, but I'm not particularly handy. :D
     
  5. MysticCow macrumors 6502a

    MysticCow

    Joined:
    May 27, 2013
    #6
    Dear lord, that thing couldn't BREATHE. It's no wonder things blew up (the infamous capacitor problem notwithstanding).
     
  6. reddrag0n macrumors 6502

    reddrag0n

    Joined:
    Oct 1, 2007
    Location:
    Canada
    #7
    Also, check the PSU in that iMac. I did one and the caps in the PSU were bad too.
     
  7. CooperBox thread starter macrumors 6502a

    CooperBox

    Joined:
    Nov 28, 2010
    Location:
    France - between Ricard & Absinthe
    #8
    Yes, I'd heard that the condos in the PSU could be problematic too, so I visually checked them at the same time. Appeared ok. (Not too easy to get inside the PSU without a 'house-breakers' tool);)
    This G5 is still performing like new, in fact probably even better, having put on TenFourFox and all the recommended 'tweaks' - thanks to this forum's excellent related posts.
    Very impressive iMac - but pity about the constant HD background noise.
     
  8. MultiFinder17 macrumors 68000

    MultiFinder17

    Joined:
    Jan 8, 2008
    Location:
    Tampa, Florida
    #9
    Throw an SSD in that sucker and you'll be pleasantly surprised by just how snappy and quiet it can be. I had a cheap, old 64GB SSD in my G5 (the same SSD in currently in my Power Mac G5), and it made for quite the system. Give it a go if you can find a cheap one!
     
  9. Jack Neill macrumors member

    Jack Neill

    Joined:
    Sep 13, 2015
    Location:
    San Antonio Texas
    #10
    See Tiger in action again would be worth it. Gawd I loved that OS..
     
  10. joepunk macrumors 68030

    joepunk

    Joined:
    Aug 5, 2004
    Location:
    a profane existence
    #11
    Same here except that I don't have a soldering thingy.
     
  11. reddrag0n macrumors 6502

    reddrag0n

    Joined:
    Oct 1, 2007
    Location:
    Canada
    #12
    If you were in the Edmonton/St. Albert AB area, i could do it for you. Easy to do once you get the screen out and see what your doing. Did one before years back. And my friend is still using it to this day as a kids computer.
     
  12. Daniël Oosterhuis macrumors 6502a

    Daniël Oosterhuis

    Joined:
    Jan 10, 2016
    Location:
    Black Mesa Research Facility
    #13
    Any tips on getting the caps out? I'm picking up a dead iMac G5 soon, which most likely has bad caps as well (or will develop them overtime, anyway), and I'm curious if there's any trick in getting them out the best way.
     
  13. reddrag0n macrumors 6502

    reddrag0n

    Joined:
    Oct 1, 2007
    Location:
    Canada
    #14
    Once the logicboard is out, just heat up the end leads with a good soldering iron. I have the board standing on it's side (with help) and i heat the leads, and with a pair of pliers, gently pull the bad caps out. After cleaning up the holes with a solder braid, then i can put the new caps in and solder them into place. Then take a pair of cutters and cut the extra length off of the legs and your good to go.
     
  14. Daniël Oosterhuis macrumors 6502a

    Daniël Oosterhuis

    Joined:
    Jan 10, 2016
    Location:
    Black Mesa Research Facility
    #15
    Thanks. Do you have any recommended temperature to run the soldering iron at during removing and replacing caps? And what kind of soldertip should be used? Just a wedge one?
     
  15. reddrag0n macrumors 6502

    reddrag0n

    Joined:
    Oct 1, 2007
    Location:
    Canada
    #16
    I had mine at 60W (i own a variable soldering iron) and my solder tip is a point. Made it easier for me to concentrate the heat on where the leads were coming through the board.
     

Share This Page