Best CPU cooler just to replace stock cooler on FX 8350?

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Also make sure your motherboard doesn't need a top-down blower style cooler to keep the VRM cool enough to prevent throttling at full load.

Agreed with others - the name of the game is surface area, and more surface area = more material = more cost. The bigger you go, the better and quieter it will be, with basically no exceptions. It's just a matter of how big and how expensive, and the Hyper212 EVO is a good balance of these factors for most.
 
Also make sure your motherboard doesn't need a top-down blower style cooler to keep the VRM cool enough to prevent throttling at full load.

 
Solution