Ok, so this is a review I read on Amazon for a model up (x5680). Also note, this guy has the Pro-E mobo (also 8.F version of firmware) and went from an i7 950, so nothing the same. haha But still...it sounds like similar recommendations regarding a BIOS reset.
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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. So I did a full BIOS reset. BAM! Worked. (I had the 950 OC'd to 4Ghz from it's 3.03) and needed to neutralize the speed back to norm. IT CAME ON! Of course I had to let Windows 8.1 know I was same user with new Chip, which went without a hitch.
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