Does it give you any error messages? At what point in the startup does it crash? Initializing ACPL effects? Initializing audio? What kind of video card to you have, what drivers are you running for it, and what kind of soundcard do you have?
Also, you should consider uninstalling 3.0.5 and downloading 3.1.2 or 3.1.3. I've found them to be more stable and they're free updates once you're on 3.0.x.