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many thanks 2informaticos I think the bios problems was solved.
but now, machine dead.
seems something wrong with PCH.
machine stuck on S5 state.
cheked pin 2 of R1800/R1801 get only 1.8V and 2.3V
with new chip, machine works fine now
Can I use the dump you gave and change the SN?
Will be there any problem in the future if doing system update from appstore?
I'm using chip from my donor board to write the dump file.
will try to write it to freshly new chip.
Will be back to you soon with the result.
Thanks 2informaticos for your help
@2informaticos with USB OSX, machine works fine after flashed efi dump you gave.
But after powering off, it giving back the 9 beeps error.
I also noticed that PCH get very hot few minutes after system ran.
is it possible something wrong with PCH that causing the BIOS corrupted?
I'm using CH341A Cheap USB programmer to read the chip. could that be the cause of bigger dump?
Here's newer dump of the original chip
https://drive.google.com/open?id=1zLugPAIYf74I7tiyEVAgmMxA1MvaJhv8
with the file you gave, machine start but then gave me stop sign when boot with the original...
this is the original bios file dump with the serial number
I check the file inside, but there's no serial number.
tried to compare with other bios file there's so many difference.
hope it still can be fix.
https://drive.google.com/open?id=1Uig4R-7pslCyRfmix5eSDzIfNJQsU9cq
Hi everyone, first post here.
Currently I'm working on 820-3115 machine that wont boot and give me 9 beeps (3x short, 3x long, 3x short beeps)
Tried to swap the bios chip from exact same donor board, now the machine starts but running very slow and other random issue.
I know its because the ME...