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Hi. Dead short on PPBUS and PPVIN_S5_HS_COMP. No liquid. Both rails beep to ground, OV. PPVCORE_SO_CPU, 1.8OHMS. CPU does not get warm when power is applied. I have PP3V42 - 3.42V. PPCDCIN - 16.25.
Should I hunt for the short or you think dead CPU already?
There is a fair chance the CPU is toast, if you have time for it you can try to hunt down which mosfet is shorting and replace accordingly, I've had about a 20% success rate on CPU mosfet PPBUS shorts where the CPU was not killed
The common fault on this are the CPU mosfets for PPVCORE_S0_AXG, Q7550/Q7561/Q7551 area. If you inject voltage you will kill the HD4000. Just remove them. this is ivy bridge not haswell so it won't get killed from a bad MOSFET the same way.
Of course it will beep to CPU Vcore as that is low resistance too. The correct question is: Is resistance from PPBUS to Vcore lower than the short to GND on PPBUS? That would confirm a shorted high side FET on Vcore.
Hey Duke. PPBUS is 0.5 Ohms to ground. PPBUS to Vcore is 1.6Ohms. Also, this is with FETs removed. And just noticed some redish probe points under CPU between C1642 and C1723.
Thanks man. Have a good night.
Well that sucks cause it is shorted and PPBUS will have gotten to the GPU and VRAM. So expect a dead GPU, 4x dead VRAM, dead U8350, Q8360/61. Minimum that will need replacing is U8350, Q8360/61. Pull them all off and measure if there is still a short on L8360.