Windows 7: Counter-Strike Source Resolution Problem

OK, so counter strike was working fine at first. Lately, however, whenever I launch it, it opens up and shows the loading screen then the screen goes black and every few seconds it flashes the main screen with bars across it. Please help.

Do you have lastest video card driver installed?

Yes I do. And as I said before it was working fine.

do you have a nvidia card ? if so this is the solution:

install newest driver
right click on desktop
go into nvidia controll panel
display -> adjust dektop size and position
use nvidia scaling

its the same thing if you got an ATI card. but i dont know the menus on thouse

i also reccomend to use this settings in the launch option:

-dxlevel 90 (set the directX level to 9, since 10 isent supported in css engine)
-w 800 (set the width of the ressolution (i use 1920, but use what you like)
-h 600 (set the hight of the ressolution (i use 1080, but use what you like)