HL2 is great BUT faces are messed up with lines

[coolkid]

HL2 is great its just the main charactures have criss crossed lines on their face. they look as iff shadows where appering in thin lines on their faces. also some times when you kill some one when you look at them with a flashlight, they are black/white when they die. i dont know why this would happen beacouse i have
2.3 Gz prozzesor
256MB 9800xt radion GRAFIC CARD
512 mb ram
sp2

and all the setings are on medium.

any suggestions