To enable hard acceleration, you need a proprietary driver from ati: https://support.ati.com/ics/support/KBAnswer.asp?questionID=3380
It looks to me like the ATI drivers only support Radeon 8500 series and higher. I have the Radeon 7000. I did find a link that said to go to a different site to find drivers (I think it was http://dri.freedesktop.org/wiki/FrontPage). Would those drivers provide full functionality? It says "no TCL" (transform, clipping, and lighting) for the Radeon 7000 on this page:
http://dri.freedesktop.org/wiki/ATIRadeon?action=highlight&value=CategoryHardwareWould this cause a problem in something like Flight Gear Flight Simulator, or other OpenGL games? If not, do I install that driver after going through the Debian Installation but before installing x-window-system? and if it will be a problem, can anyone recommend a really cheap card that I don't need anything extra to install (nvidia maybe?) that has openGL support and possibly tv out, like the radeon 7000??