You can add the GT 610 to the list of compatible cards, using this exact same fix as the GT610 is a GT520 rebrand. Only problem now is LuxMark won't run with both GPUs, it throws up a "RUNTIME ERROR: PathOCL kernel compilation error". This is strange considering nVidia list the GT6xx cards as being OpenCL compatible ?
[url=http://i.imgur.com/12QlR.png]Image[/URL]
I'm going to try the new nVidia driver for 10.8.2 now.
Update: installed new GeForce and CUDA drivers, boots fine and GT610 patch still active as NVDAGF100Hal.kext wasn't modified by the update. My subjective test - opening a 'heavy' late game save of Civilization 5 Mac - shows that performance is back
Update 2: regarding GT cards, it actually looks like the files were modified and there is no mention of any device IDs in NVDAGF100Hal.kext anymore ????