Hello, i just upgraded a dell optiplex gx280. I put a radeon hd 4350 pci-e x16 card in. Well, I'm having problems finding out how to turn off v-synch. I have gone to display/settings/advanced, but i get no tab that says the video card. Is there something else i have to download? I've gotten the most up-to-date drivers, but nothing. Thanks for any help.