820-3115 No USB activity no chime

[No-Clean]

Board came in a while back and I fixed it by reballing SMC, worked fine for over a month.

Back in here with no USB activity, I have tried known good bios and even a different EFI chip with known good BIOS but same thing.

PPVCORE_S0_CPU 1.1V

Looks like in the past someone had worked on U7400 and U6100

 

[2informaticos]

Check all SPI Bus Series Termination resistors and traces.
Try known good DDR3-10600/12800 module, one slot at a time.
Also check R7402/03.

 

[No-Clean]

R7402/03 were checked before and they are fine, know good RAM was also tested and same thing, for reference with no RAM there is no beeping sound, also when magsafe is connected to board for the first time the meter goes up to 0.04a cycles once then it starts up normally.