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in the U8400 area there was some oxidation, apparently water got in at some point!
PPVCCGT_S0G_PH1,2,3=0,693v
PPVCCSA_S0G=0.837v
PPVCCCPU_S0G=0.001v
PPVCCGT_S0G=0.667v
PP1V2_S3=1.2v
PPVCCIO_S0G=0.597v
PP1V_S3=0.995v
PP1V_S0G=0.995v
PCH, CPU and BIOS are involved in CPU core generation; as for iGPU too.
You should get aprox 0.6V at CPU core (after 5-10s) and NO voltage at iGPU core.