I have just purchased a new Mac Pro, the standard 4 core Nahalem 2.66model. I would like to upgrade this but don't know if it is possible given that I am not familiar with Mac hardware. I have a couple of questions regarding this. I would like to upgrade the Xeon X5550 to two Xeon X5560 xeon Processors as I currently have two spare. The first question is - does this mother board actually have another processor socket? i.e. is the motherboard Just like the 8 core Mac Pro model with one socket simply left empty or is it a completely different board with only one CPU socket available? The second question is I am not exactly sure that motherboard and bios cater for this chip given that it is not one specifically offered by APPLE (though it is in the same range, package and specification) but simply runs at 2.8ghz as opposed to the 2.66, 2.93 and 3.33 ghz models APPLE has available. Thanks.