It sounds like the old thermal pad is starting to let go there. Time for a thermal pad replacement kit or better yet going out and buying a better cpu cooler. Let's see what one Zalman cooler looks like at http://www.coolerguys.com/840556016472.html I have one sitting around just that one but was all silver colored with a blue led for the fan.
Don't be surprised to see a higher temp on an older Socket A model. The old case had two 80mm fans in a case close to an air conditioner and still saw temps go up due to pad hardening up. That happens often after a year or more of heavy use while others can last for years. Seeing that at idle is a main concern there. That should be down around 42-46C until loaded.
The main drawback with stock cooling is the haevier loads seen when gaming and running multimedia apps. And you ocing will bring that up further. If it's in an older style atx case those were shorter in length and lacked the room for larger fans unless you had an adapter for mounting them. A gaming case makes the room for the 90-110-120mm fans. You get far more air flow there.