Hello, I am having the same experience with the EVGA 750I motherboard, except my system temperature shows up for me as 124C. I see you are having the same trouble as I am in detecting the 12v+ correctly. I get between 7.5V and 8.4V on every program I have tried so far. (the MB and the power supply are fine, 12.2V on the 12V+) The problem is with the correct reporting of the system temp and the 12V+) In the BIOS, everything reads correctly!
Now, if you don't mind letting go of the voltage monitoring on this board, try downloading the Nvidia 'system tools' off of the Nvidia website. Their monitor is the best I have found thus far, but not all of the fan speeds are totally accurate, and the voltages are non-existant. Otherwise a good monitor.
If anyone else has found a good monitor for this EVGA 750I MB please post.
I sure miss my motherboard monitor 22.214.171.124. Too bad they stopped supporting it.