My Mac Pro 2009 4,1 was getting long in the tooth and I was looking into upgrading it or replacing it. I opted to try and upgrade it with dual procesors to be a 2010/2012 5,1 Mac Pro and dump a lot of RAM in there. It wasn't too bad of a job, just a bit tricky to get the torque correct when tightening down the heat sink. Wasn't able to find the correct torque specs so just went slow, tested and retorqued a few times before the errors stopped coming up. Its running great now and is a great machine. The extra RAM really helps; PhotoShop had no problems working with a 5 gig file with 300 layers.
Mac Pro 2009 4,1
The upgrade kit.
3.33Ghz 5680 Intel chip
Underside of the chips.
The dual processor tray
The old CPU once the heat sink is removed
Just had to clean the old paste from the heat sink
The CPU socket. Lots of little contact points.
Left the lid on the CPU. Didn't want to de-lid them.