Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

[magneh]

Hello!

Got a Gigabyte laptop, first one I see around.
Surprisingly there is a schematic for it

So, laptop is dead, no signs of life.
Takes 4mA standby and when I press power button goes up to +-50mA and back to 4mA

First thing I noticed while checking the coils is that the GPU ones show very very low resistance 0.5ohm. My leads shorted have 0.2ohm
Is it normal for these GTX 1070 chips?

Secondly, as I heard some constant clicking coming out from the PCH (apparently,hard to be 100% sure) when keeping the power button pressed down, I measured some caps on the top of the PCH, and found several ones in short.
Some measure ok, but 10 of them measure direct short to ground.
See pic, marked them in red.

Is it safe to say needs new PCH right? what else can I measure to be sure?

Thanks

[piernov]

Re: Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

GPU VCore resistance to ground lower than 1 ohm is normal for NVidia 1000 series and newer.
Measure exact resistance to ground on RTC power rail, 3.3V S5 power rail and 1V SUS power rail.

[magneh]

Re: Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

Hey Piernov!

So if I measure at the RTC battery terminal I have +15Mohm

+V3.3S I get +10k

For the +V1.0A measuring at coil V1L1 I get 45ohm

Hope these are the correct signals you are referring to, as their name are different in this board.

Given this, confirms bad PCH?
Merci!

[piernov]

Re: Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

RTC power rail must be measured after the dual diode.
+V3.3S is probably an S0 rail not an S5 rail.

[magneh]

Re: Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

RTC power rail must be measured after the dual diode.
+V3.3S is probably an S0 rail not an S5 rail.

Ok, so after the dual diode I have +3.5Mohm

and for +V3.3A_DSW (s5) measuring at coil 3L1 is +45Kohm

[piernov]

Re: Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

Doesn't sound like any of the main power rails for the PCH is shorted then.

[magneh]

Re: Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

Yes, indeed.

What you would do Piernov?
I suppose first step would be to lift PCH and confirm that caps are still shorted out of the board (and confirming there are no balls shorted of course)

And if so, order new PCH and solder it back

And hope for the best

[noder]

Re: Gigabyte Aero 15 - GA-RP65X8 - No Power - PCH?

Good day, I'd like to ask, did you solve the problem with your laptop?