ok i meant the fan on the back of the case not bottom. anyway make sure that the fans that are exhausting are the same or higher rmp then your cpu cooler fans otherwise you are just pumping hot air into the case time after time. What is your room temp btw?
btw---Note that load temperatures of 80-90°C is within the normal operating temp. The i7-950 runs hot you have good temps with your air cooler if you want much lower your going to have to watercool. 80-90 is not great but the cpu allows it.
It seems to me from what i see on the net that some 950 run cooler then others i dont know how this is possible but some people have the same setup and one runs 4-5C lower then the other. But isnt a decent load temp for a 950 45-70c?