Installed into 2011 iMac uses the same 65 watts of power as original i5 2500s. The i7 2600s is noticeably, about 10-20% faster on all processes so far after a couple of hours. Best price I could find at time of purchase. Installation is probably challenging for most people but if you take your time and use delicate care should not be a problem. Install 2-4 hours total depends on your electronic skills. Have to take almost everything out of the computer. Look up IFIXIT guide has step by step instructions.
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