that's quite a high ambient temp, I personally do not think it is worth the upgrade for that kind of pc. The only thing i recommend is getting a air conditioner for your computer room, to lower that temperature 5 or so degrees so you have a more comfortable working room, that will also give you the same effects of upgrading the cooler. 80c is a little warm, but not dangerous at all. 85 is when you need to look at lowering it as i said above.
EDIT: I now see it is a gaming temperature, and not a prime 95 (stress test) temp. 0.0"
Download prime 95 and run a blend test. if the temps go above 87c stop the stress test and come back here. (closing the window will not stop the test. You need to go file stop)
May i ask what cases are these rigs in?