I have noticed that many heatsinks with a copper core suffer from oxidation. And even though this may sound wierd I use brasso to bring out a mirror like finish. Afterwards I clean the heatsink and processor thouroughly with alcohol (get the 90 proof if you can). Also, dont use the blister pack that came with the heatsink. Buy Arctic Silver 3. If your gonna spend 60 bucks on a heatsink then 8 more on paste isnt bad.
BTW I have the same heatsink. My system is OC 1600xp to 1800xp (rated speed) at 1.82 volts. My temps with the shuttle ak31 v 3 is 34c. I dropped 20c with the previous heatsink I had.
Again artic silver 3 is worth it it helped an additional 3 degrees.
Clocker
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