Answer to "Can I upgrade my CPU on iMac from i5-2500S to i7-2600?"Hi i can confirm my iMac Late 2011 21,5” get the i7 2600 upgrade, i ve done the upgrade 1 hour ago and testing the system now. I will post my expirience after a while. What i have done, is i ve removed the dvd drive for more power safing because auf the 205W power supply. I ve noticed a very loud odd fan after this removing. The fan is running about 4000rpm.