"2009 Mac Pro upgrade to 3.46Ghz 6-Core CPU
I upgraded an early 2009 4.1 MacPro after firmware update to MacPro5,1 with a used Intel Xeon W3690 3.46GHz 12MB 6-Core 6.40GT/s LGA1366. Has the same height as the W3520 it replaced so no problems with height adjustments of the heatsink at all.
Found that the Northbridge heatsink was loose and the chip was actually cooking at 95 degree celsius - that explained my occasional PCI problems. It is held in place with two cheap plastic push-in buttons. Replaced this with screws and is it is now at 65°C.
(Broken NB heatsink plastic retainers not uncommon, posted a reminder on that last Friday with photo of heatsink/retainer location and (freeware) Temperature Monitor link.)
Audio over HDMI now works too as does 3x8GB 1333MHz Ram.
(Both benefits of the EFI 5,1 upgrade in addition to 6-Core CPU support.
Note that per Intel's W3690 specs, max memory size is 24GB "dependent on memory type". (Maybe based on 3 slots x 8GB dimms at that time?) And 24GB also listed as max for the W3680, which I think was the 3.33GHz CTO option for single cpu 2010-2012 Mac Pros that Apple spec'd supporting 32GB ram (4 dimm slots with 8GB dimms), although OWC's maxram page lists 48GB max. Historically Apple doesn't update max ram specs when higher capacity dimms are available that may work.)
In regard to the 5770 having potential problems with HDCP in pre 2010 (ref: this Apple article) - I have this card and no problems at all hooked up to an Onkyo TX-NR709, an Mitsubishi LCD projector and a Dell 30-inch for many years.
(And you used it with HDCP content OK even before the EFI 5,1 update?)
Yes I used it with HDCP material (iTunes, Blu-ray/blurayplayer 2) before the firmware update. I know because some material would not run on my old Apple 30-inch display that doesn't have HDCP.
Thanks for the info. Maybe the issues Apple noted in the past were addressed in later OS/driver updates or were not common. 5770's have been used in even older Mac Pros, but not sure how many actually used HDCP content. And HDCP isn't always trouble-free even with 'compatible' hardware chain. (FYI: A 2008 Mac Pro owner said after swapping his 2600XT for a Radeon 5770, he has seen HDCP errors with some content. No info if his Display is HDCP compliant or not.)