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Released October 2008 / 2.4, 2.53, 2.66, 2.8 or 2.93 GHz Core 2 Duo Processor

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Why will system not boot fully with replacement logic board?

I have replaced the logic board in this machine when the original logic board failed, the system installed was Yosemite. Now the machine auto reboots before completing the boot process.

I realize that this forum isn't about software, but I should be able to find out if it is and issue with PRAM/openFirmWare as support for this type of issue.

There is no info on what the problem is, just a dialog that comes up after a brief dark screen and then a light blank screen.

Does this mean that I have to re install the original system from install disc?

Update (07/04/2018)

There is a coda to this tale: I arranged for a refund for the board with the supplier (not iFixit). So I took the board out of the machine and re-installed the original board (that had serious display issues)... NOW the original board works!!

I don't know how or why but resetting the PRAM with the replacement board and booting into safe mode with replacement board changed something that allowed the original board to work. It may have been that I had to swap the heat sink component back to the original board. That may have made a difference because the heat sink paste was renewed for the original board.

On Googling, it came up that NVRAM, EFI, or SMC could be the problem. So in my case, malfunctioning display was not be hardware related at all.

The machine is now working fine with its original board.

Beantwoord! Bekijk het antwoord Dit probleem heb ik ook

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Try and disconnect from the logic board all components one by one and try starting your Mac each time one part is disconnected. Since the logic board was replaced it might be some other part is faulty and prevents system from booting. Note down what the dialog says if it appears again and let us know, it might be of some help.

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I found the install DVD from a slightly later Macbook Pro 15". So I tried to start

up from that install disc. It would not boot from the install disc.

The machine with this issue was purchased used and I did not get

an install disc from the seller.

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Reset the PRAM.

Here's how to reset your PRAM:

  1. Shut down your machine. Yes, all the way down, not sleep or logging out.
  2. Press the power button and then press command-option-p-r. ...
  3. Hold those keys down until your Mac reboots again and you here the startup chime.
  4. Let go of the keys and let your Mac reboot normally.

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Reset of PRAM did not work.

I found instructions to boot into safe mode*. The machine would boot into safe mode.

BUT, the reason I replaced the logic board to begin with reappeared:

The screen has horizontal white lines across the upper half of the screen and the

whole screen image oscillates up and down quickly.

*http://www.idownloadblog.com/2015/07/29/...

I also found instructions to boot into verbose mode** and it would not boot beyond

a certain point. Although I am familiar with Linux and BSD system boot messages,

these are new and the only thing I could determine was that it was having trouble

with some cache issue.

**http://www.idownloadblog.com/2015/08/17/...

Because the screen in verbose mode also had white stripes, jitters and distortion

the most recent text message fell below the visible board of the screen image.

Thank you time, attention and for responses;

JK

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jekillen zal eeuwig dankbaar zijn.
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