Isn't that a good thing?... I mean, if it's running hotter, it means it's utilizing your gpu more... and you admit you see from 10-12 FPS performance increase... that's as effective as a decent overclock... Try to lower the temps, but I certainly wouldn't look at that as a bad thing... Just my $.02
There is a purpose to thermal paste, yes, in theory an elevated temperature is a good thing, the real problem isnt if its running at 50-60 degrees, the problem is if it is ELEVATING quickly.
You should be concerned if you see it go from 50-75 degrees in a matter of minutes, unless you are running a benchmarking tool, in which case, (not sure if ti applies to others), but ive found it reasonable for it to rapidly increase in heat.