Harpertown Xeon do not work in MacPro 1,1-2,1
Some posts scattered on the web claimed a Intel Harpertown Xeon, like the X5470 could work in a MacPro 2,1 (or eve 1,1 - they are hardware identical, just different firmware) given they still use the same LGA 771 socket. There even is a post where someone claims that he got a voice message from Apple confirming Harpertown support for his MacPro 2,1.
However, yesterday I tried that (Mac Pro 2,1 with the newer firmware) and I can assure you they do not work. The main logic board led indicator CPUB failure would light but nothing much else would happen.
Another note: Before you pull like crazy on the front fan assembly: mine were fixed with a second screw, the disassembly guides I found only mentioned one at the main logic board, however I had a second screw holding it in place just at the bottom side, where the CPU heat sinks end.
PS: It was actually still quite good that I disassembled the beast. With the original Xeon’s it still works (puh!), and considering that after some 6 years of 24/7 server load it was full of dust and so an internal cleanup was more than overdue ;-)
