I have a Mac Pro (4,1->5,1) that I just installed a Sapphire 7950 Mac Edition card into, and I'd like to find out if anyone knows any workarounds to get it to run with official (or at least semi-official) driver support in 10.6.8. The situation is that I have two boot drives: one is 10.9.4 and the other is 10.6.8. I have to keep 10.6.8 because I have FCS3 installed on it and I have to be able to use it for some things. Of course the 7950 is fully supported in 10.9.4, but in 10.6.8, even though it boots fine and runs (mostly) fine, there is a lack of official driver support that keeps me from being able to open FCP7 (it gives me an error when I launch the app and it won't open at all). Also when I open Cinebench for example it says that the GFX board is "Apple Software Renderer" instead of the name of the card itself (it reports it correctly in 10.9.4). Odd thing is, in System Profiler it says there is a driver installed (and it reports the correct name of the card also). I glean from these things that in 10.6.8, the 7950 seems to be somehow generically supported by the OS instead of being officially supported via the proper kext files. I tried manually copying what seemed to be the relevant kexts and .bundle files from the System/Library/Extensions directory on my 10.9.4 drive into the same directory on my 10.6.8 drive, but that was a no go (which I figured it would be, but thought I'd try anyway). I also tried examining the package contents of the “RADEON HD 7950 for Mac.pkg” but it didn’t give me the option in the contextual menu. Of course when I double-click on it in 10.6.8 it says it’s not supported etc and won't run the installer. Anyway, I don’t know if anyone has any experience with this specific situation but I would greatly appreciate some help. Ideally (and maybe unrealistically) I’d like to find a way to install the necessary kext files for official 7950 support in 10.6.8. If that’s not possible, then maybe an alternate option could be installing a 7950-compatible kext for an AMD GPU that’s similar enough to the 7950 that it would make it work in 10.6.8 (essentially making the OS think that the 7950 is another AMD GPU). I’d be good with that even if in doing so the 7950 doesn’t operate at 100% efficiency, so long as it would be “officially” supported and would allow me to open FCP7. (For my purposes, this solution would be fine because I’ll be using the 10.9.4 boot drive most of the time anyway.) Or maybe there’s a way to modify an existing official kext to make it work in 10.6.8…? I’m open to any ideas so long as they don’t involve updating 10.6.8 to 10.7.5, because as I said I have to be able to use FCP7 and I don’t want to risk not being able to open a 32-bit app in any post-Rosetta OS (even though some have apparently reported that FCP will still run). I'm trying to avoid having to swap out the 7950 for my GT120 every time I want to use FCP7 (and I would have to swap it out because all my other PCIe slots are being necessarily used). So, thoughts? Thanks in advance!