There's no official support for this card on the AppleTV yet, but we've made the latest SVN build of XBMC and required CrystalHD support files available for those who are too curious to wait.
Steps to install:
1. Ensure your running the latest XBMC/Boxee Launcher (update through Maintenance --> Manage Plugins menu).
2. Download the latest XBMC SVN build (E.G. XBMC svn r.xxxxx) through the XBMC/Boxee --> Downloads menu.
3. Download the Crystal HD drivers through Maintenance --> Install Extras
4. Run Smart Installer - http://wiki.atvflash.com/index.php?titl ... _Installer
5. Navigate to nitoTV --> Settings --> Utilities --> Kernel Extension Manager. Highlight the BroadcomCrystalHD.kext, press the right arrow and select 'add to rc.local'.
6. Restart the AppleTV, launch XBMC and enjoy 1080p playback.
