Clover test and patches for Polaris GPU in Clover Posted December 22, 2016 Its already possible to use Polaris cards without an IGPU. I'm doing it right now. I have no IGPU at all (Xeon processors) and the only PCIE card installed is an RX 480. The problem is it is impossible to have preboot video AND acceleration. If the card is posted already, Sierra stops booting when it loads the X4100 kext (and the screen dies, and the RX480 fans usually slow down or turn off). If the card is uninitialized, then the X4100 kext effectively causes it to post almost at the end of the boot process and suddenly you have video and working graphics acceleration. This means, however, that you cannot actually see clover, the BIOS screen, or anything else. No video until OS X is mostly finished booting. Obviously this is less than ideal . All one has to do is prevent the card from getting posted by the BIOS/clover. One way is to have another GPU as primary, but not the only way. What I did was flash my card with a new ROM that doesn't have the legacy section anymore, then tell my bios to force the legacy option rom to be loaded. This makes it try to load something that isn't there, so the card fails to post, and the machine behaves as if it has no card installed at all. Assuming nothing gets screwed with the OS X boot process though, I eventually am rewarded with working video . Since many of the polaris GPUs have dual roms selectable by a switch, I have a working legacy rom saved in the second rom slot. If something gets screwed and OS X can't boot, I can flip the switch to get working pre-boot video and make any changes needed in clover, the BIOS, or whatever. And OS X will boot just fine as long as the X4100 kext is prevented from loading, but for working acceleration, I have to switch back to the 'hold onto your butt' (to quote Samual L Jackson from Jurassic Park) method and stare at a black screen hoping it boots. Note, I strongly discourage anyone from flashing their card, I did it because I have the ability to flash the ROM chip manually if I accidentally bricked the card. It's also possible to unbrick them by soldering a wire to short two pins on a SOIC-8 chip (the SPI flash rom). The leads are spaced 1.27mm apart, so be comfortable with that idea before attempting any thing like that . For most people, its just not worth it, its better to use your IGPU as primary or just buy a cheapo $20 video card if you don't have an IGPU. Could you please share the bios file.