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  1. #1

    Default MacPro 3,1 Won't Start?

    Hi Guys and Gals,

    Need some advise from anyone who has experience this issue.

    Just returned from overseas, so the machine has been dormant for 6 weeks. Was working fine before I left, tried to start it up yesterday and nothing. Managed to get it to fire up to the point the fans started and that's it. The power button just blinks on and off. Then if I power down and try to re start it nothing(No fans or blinking).

    I'm not sure if its a RAM or a PSU issue. Tending to go with PSU is dead.

    I did some research yesterday and the power button light blinking suggests it's a RAM issue. I have taken the RAM out cleaned and re-seated the individual RAM chips. The red lights on the RAM housing boards, blink on and off went the power button is first pressed. Which by my understanding is ok (I'm might be wrong here). The other thing is the PSU makes a slight tick tick sound, which would indict the recoils in the PSU might have run there last race.

    Anyone with this problem before?


    Mac Pro 3, 1 2008 or 2009 model
    8 core Dual Xeon 2.66Gh.z
    8Gb Ram
    3Gb AMD HD7880 GFX Card
    4 x 2Gb HDD
    1 x Superdrive

    Originally bought new, Everything is original except the GFX card and the HDD

    Any suggestions would be helpful and much appreciated?
    Thanks in advance


  2. #2

    Join Date
    Sep 2006
    South Coast NSW


    Probably not this but worth a try. Resett SMC . Turn off power at wall,unplug powercord from tower, wait 15 seconds, plug cord back in and turn on power. Press power on tower.
    Resett Real time clock. Remove power cord. Remove the the battery for at least 20 seconds. May have remove graphics card to get to the battery. The battery may need replacing.

    System Reset. With the power on press the SYS-RST switch. Its located in the upper right -hand corner of the logic board and is labelled SYS-RST.I used a long plastic rod (Skinny plastic chopstick?), don't use anything metal. If it boots after you press system rest but not from a cold start the power supply
    may need to be replaced.

    Power on self test
    A power-on self test in the computer’s ROM automatically runs whenever the computer is started up after being fully shut down (the test does not run if the computer is only restarted). If the test detects a problem, the status LED located above the power button on the front of the computer will flash in the following ways*:
    1 Flash: No RAM is installed or detected. Or, the quick memory test failed. An LED will light up • on the memory riser card next to the affected DIMM or empty DIMM slot.
    3 Flashes: A RAM bank failed extended memory testing. An LED will light up on the memory • riser card corresponding to the affected DIMM.

    There are 9 LEDS between the DIMM riser cards. From memory there is a diagnosis button you press with along plastic rod. If number 2 is yellow it indicates power is supplying trickle power. If 8 is green then all power rails are functioning.

  3. #3


    Hi RecD,

    Thanks for your reply. I tried all of the above you mentioned and still the same. I have cut out the ram being an issue. Seems the red lights blinking on at start up and off at shut down is normal, All cleaned, re-arranged and the same, so seems all good there.

    I reset the logic board, nothing happened. No reboot, Powering Down it just blinked when started up, so not sure what that means????

    I did press the button in where the RAM raisers are held and I got to 2 lights showing(Solid). No.2 Yellow - trickle power and No.8 Green - power supplied.
    All fans work (PSU, Front & Back and Video Card), so I'm getting power throughout the board just not enough to power on the system. So in down to either the PSU (Main culprit I believe) or the Logic-board(hoping its not).

    Thanks again for all your help and tips. Much appreciated

  4. #4


    OK, I got another system to exchange parts and found the culprit. Not power supply or logic board was actually the RAM risers are dead.

  5. #5

    Default having the same issues

    Quote Originally Posted by BabaLuttz View Post
    OK, I got another system to exchange parts and found the culprit. Not power supply or logic board was actually the RAM risers are dead.
    i suspect logic board though. Do you have a spare you want to sell me?

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