The netkas kext driver patches you are looking for to enable QuartzExtreme and CoreImage acceleration for exotic non-supported 48xx/49xx cards has been maintained by the "Hackintosh" community for newer OS X versions. Google "QE CI exotic" along with the OS X version number (like 10.8.5) and you will easily find it so you can enable graphics acceleration.
You will need to re-patch with every OS X revision update, a minor hassle.
You will need to re-patch with every OS X revision update, a minor hassle.