I would like to suggest you do a "search" of "overheating" in the Cooling Forum,, .. It was a while ago,, but I felt there was a trend , and I found that 10 of the latest 12 threads were folks with electric fans wondering why they overheat,, some got bigger fans but ended back with the original fans..
This was last spring to summer,..might want to check it out and save some headaches..
hope it helps