820-3476 RAM beeps on boot

[Jay]

Took a while but got my first retina board with a RAM issue. A visual inspection showed L7710 with half of the top missing (can see inside the coil) and a few solder balls on/stuck to C7714 and C7715. No other visual cues and as far as I know, these backlight parts have nothing to do with the RAM.

Is there a way to find out which RAM chip is the issue, if at all? Can other issues cause the RAM beeps on retina boards?

 

[TCRScircuit]

DDR power rails present? Case broken on a coil is nothing, BUT, it could have broke if it fell

Hmm... What else could have gotten cracked if it fell?

Ram solder balls...

DO NOT reflow them until you make sure you have all your DDR rails.

 

[dukefawks]

I bet it took an impact and ripped traces under RAM/CPU. If 1.35V is present to the RAM this board can go in the trash pile.

 

[Jay]

Not seeing them on the schematic. Assuming I should just go after everything "DDRREG"?

 

[Jay]

1.35V is present. Guess this can be marked as solved. Thanks fellas