I would say use it until the fan starts to crap out (about a 1.5-2years). The fan in the retail box is made by CoolerMaster (<A HREF="http://www.coolermaster.com" target="_new">http://www.coolermaster.com</A>) and is most likely an EP5-6I51, or a DP5-6H51. Most likly the former. These are more then fine for running you CPU in spec. But take off that stupid pad on the bottom and use some thermal grease. I don't trust those gummy little pieces of crap.
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