820-3330 kernel panic, clean board and no problems in ASD

[No-Clean]

Clean board, nothing comes up in ASD test, customer tells me that when running the Mac randomly shuts down, some times when starting up the Mac beeps as if there is something wrong with RAM, but after a few reboots it works fine for a while then it will either freeze or crash.

 

[2informaticos]

If beeps RAM error, then try one RAM module, each slot.
Give it time to test.

Install gfxcardstatus and switch to iGPU; see if stays on then.

Also test it without battery; better using known good original battery (even old, just for test).

 

[No-Clean]

Crazy thing with all the test this Mac has not shown any issues, thanks for you help.