I run my game from a no-cd crack in the 64 bit program files on a windows 7 system. I had exactly the same problem. With me, the cause was the installation of the no-cd crack. Before going through the hassle of uninstall/reinstall, it might be worth double checking the location of your no-cd crack. I spent hours downloading drivers etc, to find that moving the crack's location solved it in seconds. Since then, it's run beautifully with no crashes/freezes etc, so it is possible I promise.