Robbie86..... what you present is that you took several Z600 dual socket motherboards, and rendered the second socket unusable by dropping the processor onto the delicate contact pins at the bottom of the socket.
And, that you got a processor that was already certified to work on the Z600 version 2 motherboard (the X5672, shown in your link) to work on the Z600 version 2 motherboard.
So, the news you provide is valuable because it demonstrates how careful one must be in upgrading processors. Currently, as of almost July 2018, I still have not seen any reliable source confirming that they have one or two X5690 or X5680 processors running on a Z600 version 2 motherboard.
Here is what I can confirm for the Z400 v2 motherboards: The two fastest processors certified by HP for that workstation are the W3680 and the W3690. I have also been able to use a X5690 or X5680 in any of the Z400 v2 motherboards I have tried. The X5690 and X5680 both have dual QPI links..... the W versions likely will be just a bit faster because they only have 1 QPI link.