2915 No Boot No PLT_RESET_L

[grmacs]

Board starts but no USB activity.

PM_PCH_PWROK= 3.4V
PM_PCH_SYS_PWOK=3.4V
PLT_RESET_L =0V diode to ground there is .4V

Assuming ths board also has GPU issue...
but GPU VCORE = 1.15V and .05V diode to ground OR 4ohms (I assume low voltage drop is normal being the voltage looks right?)

 

[2informaticos]

PLT_RESET_L is required, to start communication between board chips.
What about CPU_PWRGD abd PM_MEM_PWRGD_R?

 

[grmacs]

CPU_PWRGD - 1V
PM_MEM_PWRGD_R - 1.5V

 

[grmacs]

Dah... just double checked PLT_RESET_L and its there. Still no USB activity on either port, no chime, no blips of life detected with external display.
I'm going to try BIOS. Let me know if you have any other thoughts.

 

[grmacs]

No change with BIOS.

 

[2informaticos]

Be sure to get known good working BIOS.
Also check all SPI Bus Series Termination resistors and traces.

Try disabling GPU in BIOS, to discard it.
More easy to flash GMUX.

 

[grmacs]

Assuming I would end up disabling the GPU anyway, I just went ahead and removed it and sure enough... USB data activity, so looks like I'll be able to get this board back in action. Thanks!!!