Overclocking won't make your games look better, the only thing that will do that is choosing more demanding settings in game. Overclocking your CPU can, in cases, let you do exactly that. Typically the GPU is the bottleneck in games, however, so a faster CPU doesn't buy you anything.
Also, temperatures of 80 degrees are bad for your chip. If you're going to overclock, get an aftermarket cooler and keep those temps under 60.