I find that the single most abusive thing to my graphics card is the "smooth shadow" option. If I turn that on, my frame rate will tank from 50 down to 5.
Something that a lot of us will do is we will play on low graphics settings and then we will turn all the graphics back up before entering the film viewer. The film viewer pulls the graphics settings that were last used in the game and renders the film using those. It's still GPU intensive but it's much easier on the CPU since it doesn't need to process all of the data the game is trying to throw at it.