820-00165 Green Light, No Fan Spin, CPU Gets Warm!

[dukefawks]

Only way the CPU can get hot without the machine powering on is a shorted FET allowing PPBUS to get to the CPU. Measure voltage on CPU Vcore and see how high it is.

 

[computercaverva]

I get 0V on PPVCC_S0_CPU as well as the PH1 and PH2 variants of the rail. I do have the 8.58V on ISNS Computing rail going to the FETs 7310 and 7320 I do not have any of the data lines going to the FETs to prompt them to open. I thought this was because the controllers were not being told to open the FETs and when I checked the controllers U7310 and U7320 I noticed there since PP5V_S0 is not present those controllers aren't being powered. There is no short on PP5v_S0, I guess it is possible that the controllers may not be straight to ground but still dissipating most of the voltage needed to power the CPU?

 

[dukefawks]

Remove the heatsink from the CPU and feel if it is really getting hot. If it is then find the rail that has power on it. The CPU will probably already be dead though.