+1 on better cooling for both the card and the case - cold air in, over the heat sinks, hot air out. Arctic has a great reputation, and it's really not that difficult to swap out the cooler. Also, the good aftermarket coolers tend to not only cool your card better, but also be quieter while doing so!
Failing that, you can always try a portable AC unit
Failing that, you can always try a portable AC unit