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.
Is dit een goede vraag?