As some RX480 users pointed out that they can access the recovery partition without any EFI. I jsut tested it with my 7950. I booted my Mac with the non EFI VBIOS, hold Command + R, and I can confirm that I can use recovery partition without any issue. TBH, I couldn't remember if I try this before Sierra. I don't know when this function exist. Or, I simply assume the recovery partition won't work without EFI. If my assumption is correct. That means any OOTB GPU, even not fully accelerated card, as long as it can display something in Sierra, the recovery partition is accessible. I assume the recovery partition can only load the Apple driver, however, if anyone have the non EFI Maxwell card, you may test if the recovery partition actually accessible for you in Sierra now. --- Post Merged, Oct 3, 2016 --- Anyway, it seems Apple finally moving away from their legacy EFI. A flashed GPU now basically only provide 1) the boot manager 2) a precise ident in the system info 3) may be still a requirement for the HDMI Audio to work properly Function 1 is pretty redundant, because we can easily pick the boot partition inside the OS, or use key combo during boot. Function 2 is purely cosmetic, completely an extra bonus without any real impact on any operation. Function 3 is still an unknown. And now a) Recovery partition can work with PC card b) the apple logo (loading bar) may appear during boot These 2 functions usually not doing anything in daily ops. However, now we can disable SIP with non EFI GPU. And we can see if the loading bar stuck during boot. Which are useful when something went wrong.