Hi,
Check your rfactor config tool (in the main rfactor folder or in your start menu/all programs/rfactor folder) to make sure you're set for dx9 with the correct screen resolution (sometimes this resets itself when you....) update your graphics card drivers from the nvidia site....try the anti-aliasing settings (they smooth out the graphics) in the config tool....aside of that it's general housekeeping on your pc - clear the caches, get rid of as many background applications as possible so they're not using cpu capacity (adobe reader auto-startups and such - i'd recommend you use ccleaner for the housekeeping, which has a good tool for tidying the registry and bootup for your pc).
Please note the video you attached is a modded version of the track - read his link in the blurb at the top and follow the link.....he's not running the same version of the track that you may be.