ATY_init by netkas, thats one of the latest gfx injectors for both ati and nvidia seems to work great.. i tested it once and it worked on 8500GT and 8600GT where for example nvinject failed.

You seemed to do install kext properly (if all other injectors had been removed) but you forgot to rebuild extensions' cache with kextcache command, or boot -f to force rebuilding it.

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