all voltages in the machine can vary by +/-10%
I'm pretty sure though, that you are either misidentifying the voltage you are looking at, or the software you are using is configured wrong, or it just doesn't work with your particular board.
As far as 13.5v, that is fine for a value that is supposed to be 12v, and I would not be at all surprised if you were to later find it at 11.5v or somewhere around that.
Personally, 60c under load would be a little high for my personal prefs, but it isn't going to cause any damage. I personally try to stay between 45-55c, usually around 48c is where both my AMD machines stay.