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README.md

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+Intel HD Mobile Graphics
+=====================
+
+On OS X Yosemite Intel HD4600 Mobile graphic cards are no longer supported out of the box, even when injecting a different device ID through DSDT.
+
+A [solution](http://pikeralpha.wordpress.com/2014/09/10/experimental-bin-patch-for-hd4600-mobile-gt2/) was found by Pike R. Alpha, by means of a binary file patch to AppleIntelHD5000Graphics.kext
+This patch can still be applied through Clover to prevent changes to the operating system.
+
+However an [additional patch](http://www.tonymacx86.com/yosemite-laptop-support/145427-fix-intel-hd4400-hd4600-mobile-yosemite.html) is required to enable OpenCL/OpenGL without problems.
+
+When looking in detail, both AppleIntelHD5000Graphics and OpenCL.Framework retrieve the graphics device and product ID directly from the IOPCIDevice configuration space.
+Due to this any injection though kext or DSDT is ineffective.
+
+IntelHDMobileGraphics however is able to act as a layer in between AppleIntelHD5000Graphics and the IOPCIDevice representing the graphics card.
+This allows modifying the PCI configuration data as it is read from the device, successfully making it appear as Intel HD4600 Desktop.
+
+Due to this no patches are needed to either AppleIntelHD5000Graphics or OpenCL.Framework and the Intel HD4600 should work out of the box.
+
+Currently this is in proof of concept stage, but it can be enhanced to also take care of the device ID matching.
+
+A pre-release testing build can be found in the releases section.