Invisible objects

[supraracer004]

When i play hl2 it seems there are some invisible obects. i never see them, until i accidentally move them, then i see white lines that show the way it moved. It always seems to be either select boxes or pieces of wood. I also have a similar problem when i play cs: source, just them some textures are checkered. ne sugestions?? thanx

 

[jesse_cool5]

make sure your running the latest drivers for your graphics card also try changing the resolution

 

[supraracer004]

that didn't work, still the same