I have a 20" 2.0 Intel iMac with the ATI x1600 256MB. I downloaded the demo of Quake 4 and to my suprise, it doesn't seem to support the resolution of 1600x1080. I have to play at a smaller resolution which only utilizes a portion of my screen. Is the option of 1600x1080 available on the full version? I can't see buying the game and not being able to play the game full screen. Help!