The fans won't actually turn on until your GPU hits around 60C.
When underload, anything above 80C is when people begin to be concerned about their GPU's health but i wouldn't worry unless you know its high for sure. Monitor your temperatures using the software provided by your manufacturer or alternatively 3rd party software like CAM.
As for the i5, a stock fan generally is frowned upon for intense gaming. Monitor the tempeture of your CPU whilst game with CPUZ or CAM if you are seriously paranoid. Then we can give you a clear answer moving forward.
Hope this helps