I'd like to upgrade the GPU in my mid 2011 iMac. It currently has the 6770M, which isn't great. Clearly it's possible to go to the 6970.... but is there any better (not necessarily Apple sanctioned) options out there? Every time I find a thread talking about it, there's never a final success/failure post by the OP No interest in going to the new iMac version as I don't want to lose the built in optical drive (mine is bluray and I use it for disk ripping) or user serviceability. Warranty expired, so no concerns there, either.