I have a 2010 Mac Pro 2.66x2 Xeons. I want to upgrade the CPU's in them. I was looking at the W3680 or X5680? The only real difference I've seen was the X series can run at about 10 C higher Mac temp, oh and the fact that a pair of X5680's are twice the price of the W3680. Would I notice any differences between the two (other than a potentially heavier wallet, that I would be 100% grateful for)? Anyone with two W3680's how do they run? Any issues. Thanks as always for any and/or all feedback.