Acer SF313-52 no video

[orientalsniper]

Hello all, this board is not giving me any video signal. The PCH and processor dies heat up when I power it on. Tried flashing different BIOS.



PLT_RST_N is 3.3V, but DRAM_RESET_N is 1.17V , I'm not sure if 1.17v is correct voltage, I can't swap RAM since the RAM is onboard/soldered.

[mcplslg123]

Re: Acer SF313-52 no video

DRAM_RESET should be 1.2V for DDR4-so seems correct.

[orientalsniper]

Re: Acer SF313-52 no video

Someone (FairRepair) helped me track down a very low resistance (around 14 ohms) in the VDDQ line even it's being fed 1.17V.

Since this board (NB8511) has soldered RAM, I desoldered the 4 RAM chips and the low resistance was GONE. However if I just solder back any 1 of the 4 chips, I still get low resistance.

My question is: Is there a chance all 4 chips are shorted or could another component create this low resistance once a chip is soldered on.

I have to note the VDDQ coil (PL701) is taken off, so the exact rail with low resistance is +V1P1U_VDDQ

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