With stock fan freshly installed out of box... about 40 degrees idle 55 degrees under load.
If it has already ran for a few years, dirty stock fan, dried out heat conducting paste (between cpu and heat sync) and have poor case ventilation, it can idle at 60 degrees and go up to 75 and can crash if you are converting video or doing other cpu intensive tasks.
I am not much into overclocking but I don't think this cpu is one of amd's best overclockers... you should easily hit 3ghz or a little more with the proper help and knowledge and most importantly a good after market cooler such as Artic Freezer 7