On the fritz

My lovely little PowerMac Pro is having conniptions — I suspect a bad connection to the display, because intermittently the screen will decide that white will be displayed as purple, and everything else as shades of green and yellow. It turns out that that color scheme is really hard to read, and writing is even harder. I’ve checked the obvious — like that it is one of the display options I can configure, and it isn’t — and will test it later today with an external display to see if it’s the logic board or the display board.

Writing today will depend on how long it can stay in a normal, healthy, readable mode — I don’t feel like blogging by doing the equivalent of fingerpainting in Fruit Loops tinted vomit.


  1. tallgrass05 says

    That is often a symptom of the video cord that connects the computer to the monitor or projector input. There’s often a break in the wire right where it meets the part that plugs into the computer. Jiggle it and see what happens.

  2. multitool says

    Green and Purple? Clearly the Joker is behind this!

    On my PCs, those symptoms have always been cable issues, cheap and easy to fix.

  3. slithey tove (twas brillig (stevem)) says

    IT Crowd’s Chris O’Dowd will of course say, “Turn it off and back on again. hmm”
    if it don’t help, doesn’t matter, just do it. /snark
    [love throwin IT Crowd around]
    wow, odd undiagnosable (remotely) symptoms.
    Whte displayed as purple implies loss of green, yet any other color is green or yellow (no blues)
    so mysterious indeed. simple loss of single color can not account for it.
    sorry for longwinded: “good luck. I can offer no help.”

  4. says

    It’s a mac. Cables not accessible, and nothing on this machine is ever a cheap fix.

    Right now it’s holding steady, though, so I’m hoping…

  5. says


    Cables not accessible,

    ?! I had no idea. I can’t count the times I’ve cleared up a big problem with a new cable.

  6. wzrd1 says

    As memory services, that’s an old PowerPC based Mac Pro, not the newer Intel based Mac. I have a G4 and G5 in my storage unit, awaiting transport down here. Apple dropped support on those some time ago.
    Currently, I’m using a gifted MacBook Pro 13 inch, dearly missing my 17 inch MacBook Pro. Alas, it was thirsty one night and I gave it a glass of sangria, which did the system board no good.
    This one gets cranky after a few days, likely because I have MRTG running on it and my network switches are still in storage, also awaiting transport here. That’s filling the drive with temp logs, which are flushed upon reboot.
    I also had some weirdity go on recently, where my desktop settings wouldn’t be saved and even the screensaver wouldn’t activate. Turned out that file permissions in ~/Library got munged. A bit of work, it’s right as rain, if tiny.

    Even our most devoted Apple users at work agree with me, the current MacBook line has overconverged, with the MacBook Pro being far too similar to the Air to be worthy of purchasing (and we older folks miss the 17 inch model).
    The current Mac Pro unit is anemic compared to a Dell Precision workstation, with its up to 16 cores and more RAM than the Starship Enterprise! My Dell, used when I was located in Maryland had a 12 core Xeon processor array, 64 gigs of RAM and RAID 1 drives. Apple’s offering couldn’t touch it.
    Alas, they screwed that all up by installing Windows on it, rather than a real OS, such as Linux.

    I’ll buy a new MacBook Pro when Apple provides it with a minimum of an I7 processor and it can handle at least 32 gigs of RAM, 17 inch screen and a terabyte minimum for SSD.

    Don’t even get me started on this office’s HP Elitebook units, with their microscopic 13 inch screen, 16 gigs of RAM and whose network connector shatters for unknown reasons.

    In this case, I’m thinking video cable, although the display card could be also getting flaky.

    Still, I drool when thinking of that Dell Precision workstation for home. Alas, we’re talking around $7k for the damned thing. Pity, slap Ubuntu onto it, call it a day. :)
    I guess I’ll stick with my Precision notebook and my MacBook Pro for home (although, my servers are Dell PowerEdge servers).
    Yeah, I have servers in my house. My newest has RAID 10 at 10 terabytes of storage for our video collection, which I’m gradually moving onto the array.
    Although, I really should get a couple of SAN units (you back up a SAN to another SAN, if you’re smart). ;)

  7. wzrd1 says

    For clarification, the Mac Pro basically was what should have been done with the G5.
    While, it’s an older machine, it is one hell of a machine!

    There is no such thing as an inaccessible cable, only impossibility of getting up from the floor after contorting oneself to actually reach those *@&#! cables

    I’ve found that the liberal usage of profanity helps. It doesn’t resolve the issue, but it does assist in maintaining a survivable blood pressure. ;)

  8. anthrosciguy says

    You should buy a Mac. Wait, no, you’ve got one. You should buy a PC. Or a Linux. Oh, I know: buy an Amiga 2000 with a mega-midget racer. That’s how prehistoric I am in computer flame wars.


  9. matthieu says

    Hey, did you hear of ifixit dot com.
    Many useful and well described tutorials for whatever you need to repair on your iMac or Macbook. I often use it when there are problems on the school computers.
    Thanks for your work, by the way. And hello from France. Sorry for my poor English.

  10. Nerd of Redhead, Dances OM Trolls says

    I developed a problem where when I put the display to sleep on my iMac, it would intermittently lose power. No response, not even the on/off switch. Had too turn off power to the system, then power back up and reboot. I noticed some loose USB plugs and set them properly.
    No problems since.

  11. robro says

    PZ, are you sure about the “PowerMac Pro”? I don’t think Apple ever had a product specifically by that name. If it’s a PowerMac anything then it’s really old…at least 10 years which in computer years is like an eon. If it’s a Mac Pro, then fairly current and you are very blessed with cool.

  12. Pierce R. Butler says

    PZ Myers @ # 5: Cables not accessible…

    Eh? PowerMac G5; PowerMac G4, just plain PowerMac (couldn’t find a “Pro” model anywhere in the PowerMac line).

    Those cases are very easy to open, especially when compared to, say, iMacs or the original little Macs. And they all use external displays with external connectors.

  13. robro says

    Ah, MacBook Pro…A quick dive into Apple Support on display issues landed on the page to contact support…call, chat, schedule an appointment, usw. In other words, you need a hardware fix.

    From a Stackoverflow thread for someone with a MacBook Pro where white suddenly changed to light yellow: Open System Preferences > Displays. Click the Color tab and make sure Color LCD is selected. If it is, or selecting it doesn’t correct the color, click Calibrate (to the right) to open the Display Calibrator Assistant. At the Target White Point panel, be sure to select Native.

  14. tallgrass05 says

    Oh, I thought you were talking about a desktop machine with an external monitor. My bad, never mind. If you’re talking an old PowerBook, you’ll be buying a new laptop. Back up your hard drive now.

  15. ck, the Irate Lump says

    If it’s a laptop, it’s probably just the LVDS cable that goes through the hinge. The part itself is probably cheap, but the labour required to open it all the way up to get to that cable might be prohibitive, especially the ultra-light and compact models.

  16. Dr. Pablito says

    I concur with ck@20 that it sounds like a cable wear problem in the hinge. You get much longer use out of a laptop machine if you never open it up and flex the hinge.

    But seriously, if you try plugging it into a cheapo external monitor, does it do the same thing? You’re applying some SCIENCE to the problem.

  17. unclefrogy says

    that is one of the primary reasons I do not like any of the laptop, note books or any of the portable computers. The computer is made up of a number of fiddly subsystems, I do not care what brand or architecture I have yet to see one that is any where easy and simple to work on. Brother when you stack a bunch of new fiddly stuff into the smallest box you can possibly make it fit into figure in MTBF then subject them to the real world of dirt, heat and accidents it will always follow Murphy’s law. Fortunately for me I do not have to have system that is easily portable I have nice big well designed cases with lots of air and easy access. hell I can take the dam things outside and use an electric blower to dust them out once in a while no sweat
    I feel for you and hope it is not to expensive a fix and does not take too much time.
    when my systems go down it always like I lost both legs from the knee down and my tongue and ears have been glued shut.
    uncle frogy

  18. says

    It works fine with an external monitor, so yeah, I suspect it’s the cable. I’m going to Minneapolis this weekend, may see if I can dart into a repair shop and get a fast fix. (I know I can’t get it done in Morris).

  19. wzrd1 says

    After working on my macbook pro, I found that it wasn’t as much a pain to work on as some other company’s laptops.

    As for computer flame wars, I pick on ’em all, largely because I use pretty much every OS around for different tasks.