I own a 2011 iMac (the 27", Core i5 2.7ghz model). I plan to upgrade to an internal SSD soon, but while I have the thing on the surgery table, why should I not upgrade the CPU too? I'm pretty sure that swapping out the Core i5 2500s (2.7ghz) with a Core i5 2500 (3.1ghz) or even a Core i7 2600 (3.4ghz) is completely possible. I think the power requirement should not be a huge deal for a desktop class machine like the iMac (and apple would be wise to use the same PSU and other logic board components between the 27" iMac models - to keep costs low). The difference in power requirement between a i5 2500s and an i7 2600 is very slight (65W vs 95W). Here's my question though. Ivy Bridge (coming out in Jan/Feb timeframe) is going to use the same LGA 1155 socket -- excluding the crazy "extreme 6-core" series. Ivy bridge is also going to be roughly 30% faster than sandy bridge and probably will have similar cost for parts, and with all the new tech (trigate transistors and 22nm process) will use even less power! Should I wait and gamble with the i7-2600 equivalent Ivy Bridge part? Or should I go ahead and upgrade to i7-2600 now? (will be almost 30% improvement from the i5-2500s I currently have). I would like to know your opinion. I don't mind waiting till Jan/Feb 2012, but I am not 100% sure whether or not swapping the i5 for a nice Ivy Bridge i7 would work or not. If this is hopeless anyway, I'd rather upgrade to i7-2600 now. I would also like to know if someone has actually performed a CPU upgrade successfully (in any of the 2011 iMacs).