How come in Counter-Strike Source it says 'Invalid Scan Freq' when I turn the game on?

Question

I accidently changed my video settings to I guess something that my graphics card can't handle, and now that I load up CS:S it shows that error, with blinking colorful lines all over the screen?

Answer 1

In steam, right click on the game, go to properties, find the launch parameter line and add -windowed -dx9. see if that works.