Why won't my laptop support the native resolution of my ext. monitor?

[comporanger]

I have an HP S2031 connected to a Medion Akoya 96980 laptop ( Windows Vista)as an external monitor. The video adapter is an ATI Raedon X1270 and I'm trying to use either the Windows display properties or the ATI Catalyst Control Center to change the screen resolution to 1600 x 900, which is the native resolution of my 20" monitor. Neither gives me that option - the nearest offered is 1200 x 1600. At one time I was able to get the correct resolution, but after rebooting the  computer the video would default to a lower, squashed-looking resolution. I've installed the latest drivers and software from ATI, which I suspect were not the problem anyway, since the older version of driver did briefly work allow me to obtain the correct setting.  Any help would be greatly appreciated. Thanks in advance.

[Transfusion]

The Radeon X1270 is equal to the desktop HD 3400, which will definitely struggle at widescreen/HD resolutions, so that's probably why such a resolution was not included by default.


There should be something along the lines of "add unsupported resolution" in AMD/ATI catalyst.


http://forums.steampowered.com/forums/showthread.php?t=1765387


There is also a registry tweak that helps.