Dont Buy a Used CPU! ever! Especially a chip that is known To OC well!
Besides that i would look at a slightly better Air Cooling system, the H50 Is over rated
Follow this link, choose a HSF in The top 10 (Intel Performance) And start Savinghttp://www.frostytech.com/top5heatsinks.cfm
Personal favorite is the CNPS10XQuiet... IT's a good Value vs Price component and is only about 0.02 'C over ambient different to the Noctua N4H-D18
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