820-00138-A 3 Beeps RAM Issue

[javier_herart]

Hello

I have this board, no signs of corrosion or any damage. I get voltage in all the big coils, turn on, no video and 3 beeps

Any idea?

 

[TCRScircuit]

PCH, CPU, a bad RAM chip or a missing RAM power rail could be possible differentials.

Post voltages on PP1v35_S3_MEM, PP0v75_S3_MEM_VREFDQ.

 

[2informaticos]

Be sure the 4 heatsink screws are in place.
If any retainer was bad, check for damage near it.

 

[javier_herart]

PP1v35_S3_MEM: 1.38V
PP0v75_S3_MEM_VREFDQ_A: 0.698V
PP0v75_S3_MEM_VREFDQ_B: 0.700V

4 retainers of the heatsink are fine. No damage around retainers either.

Thanks

 

[2informaticos]

Bad RAM chip, or CPU...

 

[javier_herart]

Reflow ram?

 

[2informaticos]

I doubt will help.
You may change all RAM chips and finally find CPU is the culprit.
Is more economic to replace the board.