RAM slot causing system not to boot after CPU Upgrade, Mac Pro 1,1

Discussion in 'Mac Pro' started by hcs-mac, Jan 11, 2019.

  1. hcs-mac, Jan 11, 2019
    Last edited: Jan 11, 2019

    hcs-mac macrumors newbie

    hcs-mac

    Joined:
    Apr 11, 2018
    Location:
    London, England / Zürich, Switzerland
    #1
    I am having a weird issue after I updated the CPU's on my Mac 1,1 to the quad core from the dual cores.
    If dimm 1 on the lower RAM board is occupied the system does not boot. The system turns on and the fans turn on as normal however there is no video out put and no chime, the white front LED is as normal. I have tested this with both RAM boards and it does not boot if there is any RAM in Dimm 1 on the lower RAM board. I am not sure what is causing this. I have switched the RAM around on the board and it is always the same Dimm 1 causing the issue. The board works fine with all ram in it, if it's in the top slot.
    Could I have damaged or broken a chip while installing the CPU's? I don't think I have bent any pins, I checked that thoroughly before installing the new CPU's. I have replaced many CPU's in the past and never had an issues before.

    UPDATED: After doing some tests in the system I realized only the TOP slot is working and detected by the system. I have 32GB over 8 sticks and only 16GB shows up with 7 of the sticks in. I have to have dimm 1 stick removed to get the system to boot. I am not sure what is causing this issue. There is no RAM failure LED's on the boards.
     
  2. Macschrauber macrumors 6502

    Macschrauber

    Joined:
    Dec 27, 2015
    Location:
    Germany
    #2
    Give the slot a good clean with isopropyl alcohol. Also you might search for smc update to that version of 2.1
     
  3. hcs-mac thread starter macrumors newbie

    hcs-mac

    Joined:
    Apr 11, 2018
    Location:
    London, England / Zürich, Switzerland
    #3
    I think it already updated to 2,1 and I am having some troubles trying to flash a HD 4870 512MB for it as well.
     

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