10.14.5 is now official. And I can confirm that AMD card users (Polaris or above) can enjoy H264 hardware encode / H264 hardware decode / and HEVC hardware decode. The procedure is as follow: (please read through the entire Q&A section BEFORE you do anything. You should know how to recover, or may need to use alternate procedure, etc) 1) Keep SIP disabled 2) Download Lilu.kext version 1.3.5 3) Download WhateverGreen.kext version 1.2.8 4) open Lilu.kext 5) enter Contents 6) create folder "Plugins" (N.B. This folder is INSIDE Contents, please do NOT miss step 5) 7) Copy the WhateverGreen.kext into Plugins 8) Copy the whole modded Lilu kext to /Library/Extensions/ 9) Open terminal 10) Enter Code: sudo chmod -R 755 /Library/Extensions/Lilu.kext 11) Enter Code: sudo chown -R root:wheel /Library/Extensions/Lilu.kext 12) Enter Code: sudo touch /Library/Extensions 13) Enter Code: sudo kextcache -update-volume / (you may get some strange return with this command, don't worry about it) 14) Enter Code: sudo nvram boot-args="shikigva=96 shiki-id=Mac-7BA5B2D9E42DDD94" 15) Reboot Q: Is this safe? A: Tested since 10.14.5 beta 4, so far, no system damaged by this mod. Q: Is there any down side? A: Yes, iTunes / Netflix DRM streaming may not work, but fully download DRM movie should not be affected. (iTunes and Netflix still works on my cMP with the RX580. The exact condition to make it work is unknown at this moment. But seems Chromium base browsers are OK. e.g. Chrome, Brave, Edge, etc) Q: Any other known issue? A: Photos app crash if HDMIAudio.kext is also installed. Besides, few more users reported system freeze. It seems only Polaris GPU is affected e.g. RX580. So far, all freeze only occur in Apple apps. e.g. FCPX, Photos, Compressor, etc. 3rd party apps such as PP, DV, VideoProc are not affected. However, Polaris GPU hwaccel seems perfectly stable in 10.13.6 beta by hex editing the AppleGVA file. Beside, Adobe Media Encoder seems will cause the video engine stall. Not system freeze / crash, but the video engine simply like stop working, perform extremely bad. Normal performance can only recover by reboot. Q: If my system crash after the mod, how to fix it? A: NVRAM reset will remove the boot argument, and disable the kexts. So, will effective revert your system back to the original state. Once your system boot again, you can remove the kext. Q: What's the benefit? A: Able to play some very demanding HEVC video (e.g. this one) https://4kmedia.org/sony-swordsmith-hdr-uhd-4k-demo/ This is how my cMP can play this video now. Smooth playback with very low CPU usage (please use a browser that support VP9 to watch all the following Youtube videos in 4k, otherwise, you may not able to read the details) Able to edit raw H264 directly smoothly, no need to transcode to ProRes anymore, greatly reduce the storage speed and capacity requirement. Most likely can improve productivity as well Able to edit raw HEVC directly smoothly, no need to transcode to ProRes anymore, greatly reduce the storage speed and capacity requirement. Most likely can improve productivity as well Can greatly improve H264 export speed with low CPU usage (depends on your CPU / GPU spec) Able to record the screen at 4k smoothly. As you can see from the above link. My cMP now can do those stuff and still record the screen smoothly at the same time. Able to play VP9 video smoothly. My cMP now can play 8K youtube video with zero frame drop. (VP9 only partially supported in UVD, therefore, CPU usage still very high, this is normal) Q: Can this work in 10.14.4 or before? A: NO (Update 1: One user reported that latest 10.13.6 with Vega also work with this mod.) Q: Can this work for Nvidia GPU? A: NO Q: Can this work for flashed 7950 etc? A: I don't know. Please test it for me. (Update: The answer is NO, thanks bazza5938 to perform the test) Q: Which software can benefit from this mod? A: This will provide hardware acceleration at system level. So far, all my tested software works (e.g. FCPX, iMovie, Handbrake, Compressor, VideoProc, DVDFab, DV, AE, PP, FFMpeg, QuickTime Player, VLC, IINA......) Q: If I do a NVRAM reset due to other reason, how to regain these functions? A: Repeat step 14 and reboot Q: What's the recommendation GPU? A: RX560, RX580, Vega 56, Vega 64, Vega FE. (Update: for this particular purpose, Vega is definitely better than Polaris card. There is zero crash / freeze report from Vega users yet). Q: Why not recommend the Radeon VII or RX570, etc. A: AFAIK, they all work, I just not sure how mature the overall support is (as a GPU). Q: Is this QuickSync? A: NO, QuickSync is the hardware acceleration for Intel iGPU, not the generic term for GPU video hardware acceleration. AMD GPU use UVD (Unified Video Decoder) for decoding, and VCE (Video Coding Engine) for encoding. All this will be controlled by VideoToolBox automatically in macOS, virtually transparent to users. It's the same concept as QuickSync, but not QuickSync. Q: I can see that my GPU is working in Compressor before this mod (on a cMP). Is that mean I already have hardware acceleration? A: NO, we are talking about H264 hardware acceleration here. Not the general compute hardware acceleration. They are completely different. Q: How's the quality of the hardware encoded video? A: Not as good as software encoder in general. But if at high bitrate, the difference isn't noticeable. Q: When will we able to get HEVC encoding as well? A: I don't know. But you can always boot to Windows and use HEVC hardware encode. Q: How much improvement can I expect? A: Well, depends on usage. But a quick iMovie 4K H264 export test shows a Vega 64 can reduce the export time from 6:19 to 1:25, which means reduced the export time by ~77% (on a dual X5680 cMP). Q: Why VideoProc shows no HEVC decode after the mod? A: I don't know why, but this is normal in this case. My recommendation is to download demo HEVC video from the above link, and play it via QuickTime (or simply via Finder preview). As long as the CPU usage only stay around 20% (but not 800%), that means HEVC decoding is working properly. Q: Should I install the newer version of Lilu and WhateverGreen? A: NO. Despite the newer version can work, but provide no extra function in this case, and I have no idea if the newer one has poorer stability. If I found a better way / kext to use. I will update the post accordingly. Q: I experienced system freeze, Console log shows "GPU Restart" event, what should I do? A: PRAM reset will bring your system back to normal. If you are with Polaris GPU (RX560, RX570, RX580, etc), it seems some people are affected by this bug. What I found is an alternate method by directly hex edit the AppleGVA file seems more stable for these GPUs. Initial test shows very safe to do so, even I completely destroy the AppleGVA file, the OS can still boot to desktop. If you prefer to go this route, please make sure you know how to restore the file (or even completely recover from an unbootable OS). The info is at post #205. Q: How do I know if hardware acceleration is really working? A: My suggestion is by using Terminal. Detail info in post #273.