i selected it from the list of available resolutions ...pretty sure it is just driver related (based on what monitor says it can do).
I am sure you can select custom res. with newer drivers.
I am stuck, tho, using ATI cat. 3.4 -as it is the only one that works for my ati 9600 pro and other system components i have. I can not do custom settings with the driver i have.
As for monitor settings ...things like auto adjust i can't do as it is greyed out if using a dvi cable..which i am. But so far, i have not seen the need to adjust anything ...it is awesome right out of the box.
The monitor seems to have a dual dvi link input ...but the cable is only single. So i am not sure if it can do dual link dvi.
yes...the res 1280 X768 does fill up the entire screen..no borders (with my poor eyes, it is a very nice resolution

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i believe this monitor's default is to let software handle it all. And my only driver software feature for this..has scale to fit image clicked on. And however it does it, i can discern no stretching...as every thing is scaled to fit monitor (exception being dvd movies --which still look very impressive to me)
bottom line: I love this monitor! (just keep in mind it is my first lcd monitor ..aside from looking at friend's LCD lappie screens or a dell 19 inch one)
edit: played countersrtike in 4:3 (1024*768) and widescreen 16:10 mode. I did not notice any difference between the two ... aside from the obvious difference