I would do this, pull the stock heatsink off clean the TIM on the cpu and the heatsink with a coffee filter and Isopropyl Alcohol first, see if anything changes. The stock one should be doing a better job of cooling that chip, then it is. I would think the heatsink you linked would be better then the stock one but the CM 212+ will be better then the Arctic one. The Coolermasters have Mail in Rebates pop up on the Egg often, if getting a new heatsink is going to be the solution. I'd wait for the CM to go on sale, I've seen the 212+ go on sale for 29.99 with a $10.00 Mir and the Evo $34.99 with a $10. MIR.