70c

i am looking to buy a hsf (second hand or new) currently i get temps over 70'C @3.6ghz on my 1090t with stock hsf i am using a cheap silicon based paste, that is why temps are higher, while stock paste gave me 60'C temp at same setting and 70'c on 3.8ghz 1 . so how much difference i will...

i am using 8600 gt 512 mb DDR3. when i start my system the temperature of my gpu is showing 56C and when i play any game(fifa 09) it is showing 70C. is the temperatures are normal? my cabinet is fully closed.i. found these temperatures using speedfan.