We all have this problem in the summer, however good our case cooling is, the temp still goes up.
Interested to know how you solve this problem and keep the pc running nice and cool(and quieter as fans don't need to do as much work).
Only mention this as I noticed today my pc is noiser than normal(cpu hit a massive 40c when surfing the net, not high I know but higher anyway, my normal temp is 3-4c lower).