I have seen some people most that they have been able to mix different speed CPUs in a system. For example, 2 1.9GHz and 2 2.1GHz where all 4 CPUs will run at 1.9GHz. What about different amount of cores? For example (2) 8 cores and (2) 12 cores. Would that result in 40 cores or 32 cores? If that is possible to do that, what make/models support it. Uncle Sam was a little more generous this year( or I was more of a dumb ass for paying too much ) and I am going to switch my SM dual 5649s to a 4P setup. I am eyeing those eBay 8 cores for $149 each.