Alright a few months ago I had bought Left 4 Dead for the PC and the installing went alright. Steam runs fine but as soon as I went to play it, it says that my video card is unknown. I have no clue what to do... Do I need a new video card? My Driver Details: OS Version: Windows Vista Description: SiS Mirage 3 Graphics Version: 126.96.36.19952 I have no clue what to do and I tried to search up anything similar but there's no luck. I need instructions what to do because I'm so confused. [Note: The opening scene works fine but once I get to the main menu it lags only a little but the other menus somewhat lag and the loading of the game and playing lags way too much then sometimes it just crashes and my desktop pops up again.] If I need a new video card, how much [appox.] would it be?