Three fans!
Its extravagant!
I am running one fan in the S80b I have and the temperatures I have are what you would call very good.
The PC7+ is bar the Eclipse probably the best cooling mainstream case, will absolutely decimate anything with more than two fans in a db : cooling comparison; the cooling is just right.
Anything you put in that case with just the 2x 120mm fans it will cool, if anything the 80mm fan should not be used due to it adding extra noise with a negative impact on the actual flow of air in the case to the PSU.
If you have an overheating system in the PC7+, I can say with 100% certainty that it is not the case. 2400xp thoroughbred in one with a passive CPU cooler and 5v fans tells me that, still got issues with the graphics being passive at the same time but its certainly interesting to know just how well this case can cool.
It is better at cooling than any other case in Lian Li's range at the moment on air bar maybe the G50 depending on your system.
It certainly is a match for any of Thermaltakes current offerings, the best of which cooling wise I would say is the Soprano which is a good comparison with the PC7+.
More fans does not mean better cooling, most likely the opposite of that with most comparisons. (Exception being an original stacker with certain setups with lots of hard drives.)