Summary: Replaced my i7 950 with this in my MSI x58 Pro-E motherboard (Last Firmware 8.F) At first the computer fired up and all, but nothing woke the screen up. Scared and worried I ran around the web trying to make sure I had compatible hardware with this Xeon. Couldn't find anything.
Summary: I installed a pair of these in a 2010 Nehalem Mac Pro. Geekbench CPU score went from 15,500 to nearly 31,000. Happy days. NB: some (not all) mac pro models will need the correct firmware to use these CPUs. Install is easy if you follow instructions on YouTube.
Summary: In 2011, a single pc with this processor took 371 days to calculate pi to a record 10 trillion digits. It also had 96GB of RAM and about 50 TB (terabytes) of hard drive space (after numerous HDD failures).