Yes this works with my build (i7 6700K + RX 460) and leads to a dual monitor setup in OS X. Use the "Mirror Displays" checkbox in the systemconfig to avoid a second screen you can't see.
Hi - I'm signing in for the first time. I'm a self-admitted noob here - I've always purchased and owned real Macs since 1987. I have been following this thread, as I have been presented with a maxed-out Dell XPS 8500, and am trying to screw up the courage to attempt this. I've owned hand-me-down PCs, even back in the days of Windows 3.1, so I have some experience with forcing hardware to work on the non-Mac side.
The graphics are Intel HD4000 with HDMI output, and AMD HD Radeon 7770 (2 GB). All Dell OEM. From Page 1 of this discussion, it looks as if the 7770 can be used without a fake ID, at least if I apply either of 2 fixes for the black screen at boot issue that crept in with Yosemite 10.10.3. I admit I am still trying to wrap my head around framebuffers.
But with regard to the El Capitan/ Sierra sleep issue - where and when do you set iGPU = primary? In Dell BIOS, UniBeast, Multibeast, Clover? And, if that is set, would the Radeon wake from sleep, or do you see iGPU output only when you wake from sleep? If I interpret what I am reading here correctly, it appears that the
iGPU does not wake up after sleep, but will function again upon reboot, and if I connect it to my display via HDMI, I can even see BIOS, boot options, etc.
Am I interpreting your post correctly?