Well for idle temps, that just fine. It's the load temps you should be worried about....
Use a program called prime95. What it will do is stress your cpu to 100% and will heat up your cpu. After about 10 mins look at what the temps are. That temp should be the hottest the cpu can get.
As long your temps are in low to mid 70C's (or lower) for max temps, you'll be just fine.
ive done this with burn in test for 2hrs and maxed out at 71c with my max o/c of 4.1 with a 1.504 voltage intel says that 71c is safe for this processor but i figured the idle temp would drop with a lower clock