A: There are certain requirements for RemoteFX, including that GPUs support a minimum of DirectX 9.0c and DirectX 10. Microsoft will be rolling out a logo certification program to recognize graphics card that are optimized for RemoteFX, including specific driver versions.
For now, Microsoft has a site that lists some information on GPUs that are focused around RemoteFX in production environments. In a lab environment, more basic GPUs will most likely work, but the experience won't likely match what you'd get if you were using a GPU and driver targeted for RemoteFX use.
Also, don't forget that your processor must support SLAT for RemoteFX to work.