Delidded Pair Intel Xeon X5680 3.33GHZ CPU Mac Pro 4,1 2009
* 4,1->5,1 firmware update program. You can download from github. Just google "github MacProFirmwareToolUpdate".
* 90% alcohol chem pad and thermal paste. You can buy from most electronics stores.
Install guide: https://www.youtube.com/watch?v=Et29f4uTLPs
Note that for testing we used pencil eraser and then used 90% alcohol to clean the pin contacts before install. Just in case it cannot boot for you, the first thing I’d try is to clean them again. Any questions about installing it are very welcome.