That model came with both ati and nvidia graphics options apparently.
Which one do you have?
It's a widescreen so I doubt 1024x768 is the real native resolution as well.
It's actually 1280 x 800
Odds are you need to track down updated graphics drivers
though (for both display and system stability). If you could provide just a little more information on the graphics card I'm sure someone could point you to it.