Mjellow I recently got my first Mac, a Mac Pro 3,1, so I'm pretty much a Mac newbie... It's equipped 2x ATI 2600 XT's and is currently running ML 10.8.2. But it just so happens that I have a couple of HD 4870's lying around, so I thought about flashing one of them to boost the gfx performance. And now comes the question: Is it still possible to use a flashed pc-card in ML 10.8.2 and if so, which guide/tools should I use? The card I would like to use, is this Sapphire 512 MB one: http://www.sapphiretech.com/presentation/product/?cid=1&gid=3&sgid=567&pid=265&psn=&lid=1&leg=0 Hope you guys can help me!