Clutter's Frequently Asked Questions
Q: Which GPU are required to use Clutter?
Really short answer: it's complicated.
Short answer: any hardware with drivers capable of supporting GL 1.2 plus the multi-texturing extension, or GL 1.3, is required to run Clutter. Alternatively, any driver providing support for GLES 1.1 or GLES 2.0.
Long answer: there are too many subtly different GPU models and drivers that fail to properly implement OpenGL or OpenGL|ES, and this makes creating a list or a matrix of supported hardware, driver and operating systems basically impossible.
For X11, the best chance is to check the Mesa project wiki for the various drivers supported.