820-00426 no brain

[Kyle93]

This arrived with no liquid damage.Customer claims this was working fine until it was hit by a lightning strike. Fan spins CPU gets warm but no other activity.

With board only on the desk and OSX thumb drive no light appears on thumbdrive.

Already tried a known good bios with clean me but no change. Vcore is 1.8v

Anything else worth checking or does it sound like bad CPU??

 

[2informaticos]

Maybe changing PCH.
Do you get PLT_RESET_L?

 

[Kyle93]

yes PLT_RESET_L 3.4v

 

[2informaticos]

Any cable connected to it, when happened?
PCH should be affected, as having direct connection with I/O interfaces.

 

[Kyle93]

3.4 v was measured with board alone on the desk.

Customer claimed was using the machine when it happened.

Should PLT_RESET_L be remeasured with everything connected?

 

[2informaticos]

I was asking if machine had any external device connected when got the lightning strike.
Not when you've measured on the board.

If doesn't revive changing PCH, then must be bad CPU...

 

[Kyle93]

Changed PCH with a new one but now only right fan is spinning and still no usb activity.

Must be CPU then? Customer decided to get new device before PCH arrived for this one and never answered our question about any external device connected when the strike happened. We still have device here since it was donated to us if you have any more ideas.

 

[2informaticos]

Looks like lost cause...