[DjNDB]

You could try if a clean boot helps. If it doesn't please post a dxdiag log.

Booting clean in Windows Vista / 7:
1. Click Start --> Type msconfig --> Press Enter
2. On the General tab, choose Selective Startup
3. Uncheck Load Startup Items
4. Select the Services tab
5. Check Hide all Microsoft services
6. Click Disable all
7. If running the game on Steam, re-check the "Steam Client Service"
8. Click on OK
9. Click Restart.
10. After reboot, run the game to see if it works.

After performing the necessary steps, restore your system by doing the following:

1. Click Start --> Type msconfig --> Press Enter
2. On the General tab, choose Normal Startup
3. Click Ok
4. Click Yes, when asked to restart your computer

dxdiag
Windows XP: Go to your start menu and click on run. Type in "dxdiag" and hit enter
Windows Vista / 7: Press the windows key on your keyboard or click on the start menu. Type in "dxdiag" and hit enter.

Now click on the button that says "save all information".
It will prompt you to save a file. Save it where you can find it.

Open the file and press Ctrl+A followed by Ctrl+C to copy the contents, and paste them in a reply by pressing CTRL-V.
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