I’ve checked DX. It’s installed properly and working (DX11). Looks like a Windows 7 problem, because Renoise runs without problems under Windows XP on the same machine…
Looks like a driver problem. Guess you also won’t be able to run any other directx based apps on your computer. Try if there are alternative drivers, especially GFX drivers available for you machine.
Renoise basically works on Windows 7 (I’m typing this on a Windows 7 RC1 right now). So far you are the first one with such a problem.