DRI Status
If your hardware is not listed then it its 3D features are most likely not supported or work is in very early stages of development. Note that some vendor pages might be more up to date than chipset pages, and vice versa.
Links:
- RadeonFeature (X.org wiki): Status of ATI/AMD Radeon 3D features among else
- FeatureMatrix (Nouveau wiki): Status of Nouveau drivers
- GalliumStatus (X.org wiki): Status of Gallium3D Pipes and State Trackers
- FeatureMatrix (outdated): Detailed summary of DRI driver features for a card and all supported cards
- Listing of 3D chips and their capabilities