I own a LG 25UM58-P 21:9 aspect ratio that can support 2560x1080.
Can my ASUSF3Se with ATI MOBILITY Radion X2500 Graphics card support this?
I cannot find a specification for this card.
The problem comes from the fact that that monitor only has HDMI, and your laptop does not, so even with a VGA to HDMI adapter you couldn't get 2560x1080. On top of that is the fact that that laptop is older than dirt and unsupported, so you should really upgrade it.
The laptop has DVI-D
I know that Radion X2500 supports 2560x1440, because I have Crossover 27q-led 2560x1440 (16:9), and there are no problems.
But I cannot configure 2560x1080.
You may try to make a custom resolution
1.AMD and ATI How to Edit Custom Resolution - YouTube
-First go to AMD catalyst and look under Information, then Software.
-Look for the 2D Driver Path. Make a note of the Path as you'll need it later.
-Go to start menu search for RegEdit
-Open Regedit as Administrator (You must open as admin otherwise regedit will not save changes).
-Open the folder as described in the 2D driver path.
-Look for a registry file in that folder called DALNonStandardModesBCD2 click Modify then add your chosen custom resolution to the list. (Mine was for 1440x900 14 40 09 00 00 00 00 60 - the last two digits denote refresh rate)
-Check Windows display and Catalyst Control to see your new resolution
2.Adding Custom Resolutions ( AMD ) - YouTube
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