If its running hot and you have had it a while, take it out and blow all the dust from the fan and heatsink with compressed air. you can also get msi afterburner and adjust a custom fan profile so the fan runs faster. Also, you live in Australia and its summer, dont run it on hot days if you dont have air con in the room. make sure you have adequate cooling in the case, at least a couple of exhaust fans to get the hot air out. If your going to spend any money now, spend it on more ram and more airflow for your case, or a better, cooler case.
While gaming for awhile when you see 80°+ degrees on the GPU touch the top of the case near the PSU, is it hot too? it might be your PSU the source of the heat not the GPU/CPU, in that case you need a new PSU. (i'm having same problem now)