820-3115 Wont Boot with 9 beeps

[RAK10]

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 region problems.

is there any way for me to fix the original bios file?

Thank you.

 

[2informaticos]

Did you search clean ME dump on the forum?
If doesn't exist, upload your file somewhere and post a link...

 

[RAK10]

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

 

[2informaticos]

No idea how did you get a dump bigger than 8MB!!!
I recommend you to read the chip again.
Just to see if Fsys area reading is consistent; because right there is corrupted.

In the mean time, try this as is, do not change serial yet; just for test...
https://drive.google.com/open?id=1qnb7ffaAKOpryPEZdEqO_Ll-yKwbVXCG

 

[RAK10]

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 drive.
But I can install new system to another drive with the machine.

 

[2informaticos]

Start USB OSX and check if machine works fine.

Last dump has correct lenght, but Fsys is also corrupted.
Do the test above mentioned.

 

[RAK10]

@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?

 

[2informaticos]

Write that dump on other chip.
The original could have internal issue, especially if is MX25L...

 

[RAK10]

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

 

[RAK10]

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?

 

[2informaticos]

Change ssn now, if confirmed to work good.

 

[RAK10]

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

 

[2informaticos]

Post =PPVRTC_G3H_PCH voltage.

 

[RAK10]

=PPVRTC_G3H_PCH give 3.331V on my meter

 

[2informaticos]

Check correct value of R1800.
If good, put good flux and reflow PCH.
Be carefull, dont kill it; no need to melt the solders...
You may have luck and is just crap underneath PCH.

 

[RAK10]

machine back to start after PCH reheat with flux.
Thanks again 2informaticos !
I think it solved now.