HP 15-CB007NT - DAG75AMBAD0 REV:D powerdown after 4 seconds

[hexadecimal]

hello, mainboard is KABYLAKE version and i tried all bios version,, when i write not kabylake bios: and ram removed board is power on, but powerdown after 4seconds when ram installed..
kabylake version bios: powerdown 4sec ram installed or not installed..

all core voltages ok.. rsmrst and powerok voltages ok..

please help, thank you

[Sephir0th]

Re: HP 15-CB007NT - DAG75AMBAD0 REV powerdown after 4 seconds

What about PLT_RST#? Link to schematics?

[hexadecimal]

Re: HP 15-CB007NT - DAG75AMBAD0 REV powerdown after 4 seconds

What about PLT_RST#? Link to schematics?

Hi, thank you for your support

PLTRST# signal is 3.3v for 4sec, when i press power button.
and
CPU_PLTRST# 1.00v

[Sephir0th]

Re: HP 15-CB007NT - DAG75AMBAD0 REV powerdown after 4 seconds

Good, and how is it in the GPU circuit? All voltages present here too? GPU_CORE and 1.35V VRAM for example?

[hexadecimal]

Re: HP 15-CB007NT - DAG75AMBAD0 REV powerdown after 4 seconds

What about PLT_RST#? Link to schematics?

Good, and how is it in the GPU circuit? All voltages present here too? GPU_CORE and 1.35V VRAM for example?

yes, all gpu voltages ok about 4-5secons..
gpu memory coil at 1.35v
nvvds coils at 0,80v

gpu core voltage graphic ______/--------\__/--_______

[Sephir0th]

Re: HP 15-CB007NT - DAG75AMBAD0 REV powerdown after 4 seconds

These "shut down" issues after all voltages are present and reset Signals deasserted are the worst to diagnose.

I don't have really good ideas left for you, except visual inspection of the whole board. Look for something like corrosion or cold solder joints.