A1466 gone wrong RAM upgrade

[iMuhtaseb]

hi

had this 820-00165 2015 MacBook Air with 4GB of RAM.. i thought of upgrading the RAM to 8GB from the pile of donors that I had..

I took a known-good 4 pairs off of a board and reballed them and put them to my board.. the computer refused to spin or power up.. I found out there was a short on PP1V2_S3.. I mistakenly injected 2 volts into it lol..

Removed short, fan span but nothing appearing on screen whatsoever..

I took another 4 pair from another board and put them to my board and still not powering on..

its consuming half amp on bench PSU.. I can feel the CPU heating up..

I've also taken the RAMCONFIG into consideration and I've aligned them perfectly and I've even matched my board to the board I had previously..

I tried PRAM resetting.. its refusing..

My board was known good and I've tested before.. what could have gone wrong?

[reformatt]

I'd be checking components around the RAM for solder bridges and movement. Especially in between each chip.

[iMuhtaseb]

I'd be checking components around the RAM for solder bridges and movement. Especially in between each chip.

that's a good hint thank you..

I actually found a short on resistor R2720 MEM_A_CKE<3>.. I removed the associated ram module, reballed it and put it back; short gone but still exhibiting the same thing.. fan spin.. cpu gets hot nothing on screen..