Apple Mac Pro 5,1 CPU Tray - 12 Core Xeon X5690 3.46Ghz, 128GB OWC RAM
This tray should be a simple plug-in upgrade to any 2010 Mac Pro with firmware SMC 1.39f11. It is not suitable for 2009 Mac Pro 2009 series. In theory it should also work with 2012 Mac Pro 5,1 models, but I have not tried that.