cMP 5.1 - how to test temp probe on CPU heatsink?

[phoenix.factory]

Hi,

a friend of mine tried to upgrade his dual CPU 2010 cMP and it turns out like it failed. The guy won't start the the 2 CPUs attached.
He took it to my place and I first tough it could be some bended pins on the CPU socket but CPU B looks nice and that's exactly when we attach the second CPU that the boy won't start.

Only CPU A attached, then it will POST (with fans spinning like crazy obviously)

I attached both heatsinks without CPU B and AHT sends 4SMC/1/40000000: SMC

This could be related to a heatsink probe fault but I don't have a spare heatsink B for testing. Tried to measure the values of the pins 1-2 3-4 5-6 on both heatsinks. They send similar values
1-2 open
3-4 4 MOhms/ 7 MOhms
5-6 5 MOhms

any brilliant ideas??

 

[h9826790]

Hi,

a friend of mine tried to upgrade his dual CPU 2010 cMP and it turns out like it failed. The guy won't start the the 2 CPUs attached.
He took it to my place and I first tough it could be some bended pins on the CPU socket but CPU B looks nice and that's exactly when we attach the second CPU that the boy won't start.

Only CPU A attached, then it will POST (with fans spinning like crazy obviously)

I attached both heatsinks without CPU B and AHT sends 4SMC/1/40000000: SMC

This could be related to a heatsink probe fault but I don't have a spare heatsink B for testing. Tried to measure the values of the pins 1-2 3-4 5-6 on both heatsinks. They send similar values
1-2 open
3-4 4 MOhms/ 7 MOhms
5-6 5 MOhms

any brilliant ideas??

I don’t think heatsink B temperature sensor failure will stop POST. If that’s true, then a 2010 tray should able to boot on a 2009 cMP. But reality is it can, just the fans run at full speed (because can’t get the temperature reading).

Did you try swap CPU yet? I mean CPU B in socket A.