10 Replies Latest reply: Mar 12, 2013 5:11 PM by btwardy
btwardy Level 1 Level 1 (0 points)



Recently my Mac Pro started to have problems. It would run very slow and freeze up for a few moments but would recover. After awhile it then started to give me another problem. While I was using it, the monitor would start to become distorted and it started to get to the point that the monitor would go to complete distortion and the only way to recover the picture would be to put the mac to sleep and awaken it. I shut it down the other night and ever since then I have not been able to get it to boot back up. It will turn on, I will hear the drive start up and continue to spin but it does not make startup sound and the monitor does not turn on. I have done some searches and I have come across that this indicates one of several problems:


1. Drive is corrupted

2. Bad Video Card

3. Motherboard is bad


I was attempting to boot from my install CD to run some tests on the Disk to see if it was bad however it wont even boot from the disk. 


Any suggestions on what could be causing this?

Mac Pro, Mac OS X (10.6.8)
  • Grant Bennet-Alder Level 9 Level 9 (53,495 points)

    "A Mac that will not boot from an appropriate Installer DVD has a Hardware Problem."


    The DVD is an incorruptible source of software. If it won't boot from the DVD, it's Broke!


    Does the power-on light flash when you start it up?


    This is the 65lb tower? What model or what year or what speed memores or something that will help Readers place it in the model lineup?

  • btwardy Level 1 Level 1 (0 points)

    The power light turns on like normal and the fans run and the harddrive spins however I do not have any signal being ouput to the monitor and it dosnt even make the startup sound.


    Here is a link to the Specs of my Mac: http://www.everymac.com/systems/apple/mac_pro/specs/mac-pro-quad-2.66-specs.html

  • Grant Bennet-Alder Level 9 Level 9 (53,495 points)

    You have a Mac Pro 1,1 from about 2006.



    dosnt even make the startup sound.

    The chime is generated in software after the first part of the Power-On Self Test has executed and passed. Memory problems here will start the power light flashing.


    Your should first do an SMC Reset. Your Mac may have a tiny pushbutton inside to do this. Test again.


    Without the chime, you can do nothing. Conventional wisdom is to remove anything that may be dragging down the power and go for the chime.

    Remove AC power. Remove the Hard drive, the DVD reader, the graphics card and any other PCIe cards, and drop back to one pair of RAM DIMMs in the first two slots on the first card.


    Restore AC power and test with all this stuff removed.


    -No, deep trouble. Check for 12 Volts and 5 Volts at the Molex that runs the DVD Reader.

    -Yes, try the graphics card back in and test again.


    continue to add an item at a time.


    One more item that may be trouble -- the BR2032 PRAM Backup battery (coin cell). A new one measures a bit over 3 Volts in hand. Substantially less need to be replaced for trouble-free operation.

  • btwardy Level 1 Level 1 (0 points)

    I let the Mac sit for a day or so and tried and it is booting up now however it is running very slow and sometimes freezes and Im having the problems with the monitor distortion still. Any thoughts on what may be causing these problems?

  • Grant Bennet-Alder Level 9 Level 9 (53,495 points)

    I let the Mac sit for a day or so

    With AC power cord plugged in, or not?


    If not, you have done an SMC Reset:

    Remove AC power.

    Let the capacitors bleed down (or push the start button for a quarter minute to bleed them forcefully).

    Restore AC power.

    Wait a quarter minute,

    Attempt to restart.


    You may be having trouble with that little coin cell battery. Next time you are in there, try removing it and measure its Voltage. If you don't have a meter, the kid at Radio Shack does, and would love to show off for you.


    Running slowly can be caused by not enough memory, or by not enough memory combined with a Hard Drive that is not feeling well. Got current Backups? if not, that should be top priority.


    If you are getting actual kernel panics, those reports are stuffed in temporary RAM and copied into a Console log later. You can pull them back and look at them.

  • btwardy Level 1 Level 1 (0 points)

    I did the reset it did not work

    I tried replacing the battery that did not work.

    Even if the Hard Drive is bad that does not explain to me why it will not let me boot from my install disk. 

  • Grant Bennet-Alder Level 9 Level 9 (53,495 points)

    Sometimes a bad graphics card can preclude booting.

    Sometimes a bad hard drive can preclude booting.


    That is why the conventional wisdom is to take everything out, then work back up from the chime. (I described that in the entries above on the forums).

  • btwardy Level 1 Level 1 (0 points)

    So I did as you said I believe that Ive determined that the graphics card is the cause of the problem. Now the question is do you have any suggestions on a suitable replacement card for it?

  • Grant Bennet-Alder Level 9 Level 9 (53,495 points)

    New from Apple or reseller, the Apple-firmware 5770 (about US$250) works in all models of Mac Pro, despite their endorsing its use only in the 2010 model. Drivers are in 10.6.5 and later.


    From eBay, seller Macvidcards sells two used models of the Mac Pro GT120 -- one for 2008 and later, one for earlier (2006, 2007), for about half that price. The GT120 requires no aux power cord inside the machine. This seller knows the requirement for the Mac Pro and seems to provide "the right stuff". Just include his seller-name in the search.

  • btwardy Level 1 Level 1 (0 points)

    Thank you very much I bought from the seller you recommended and everything is running smoothly now. Thank you!!