Windows 7 - ATI Radeon X1550 - wrong display size

Just installed Windows 7 - and now my second display won't show the correct size. When booting the computer the picture fills out the entire display, but as soon as I have to logon to windows it decreases to a sad sad size which I'm completely unable to change What to do?

// Jacob

I assume you have Catalyst Control Center installed? If you do, start it; click the GRAPHICS tab at the top left; select DESKTOP DISPLAYS in the drop down menu; click the black triangle of the display you want to change the properties of; click PROPERTIES in the drop down menu; select the resolution for your display; click apply, then OK.

In Windows: Right click on an open spot on your desktop; select SCREEN RESOLUTION; select the screen in question and choose resolution.

Under dispays in device manager are both your dispays showing up as what they are or is your second dispaly showing as PNP? If so try installing the diriver for that dispaly, this will usualy set it to it's native resolution. Fabe

thanks both. It dosn't work though...
My first display is a 19" Samsung screen - this one is clearly recognized i catalyst and also defines as my 1st/main display. The second display is my 40" flatscreen in the living room - a samsung - just recognized as 'Samsung' in catalyst. However both displays is on the same 'line' when presented in catalyst under 'Display options'. In device manager only the graphic card is showed - not the displays.
I unfortunately think it's a Windows 7 problem. As described the screensize on the 40" flat screen is much smaller (with a thick border around) smaller with no options to resize.

Are you sure the Samsung does not require a driver?

with vista it didn't but I can try to look for drivers

Bought a new card (4350) - better but not excellent.
For some reason it identyfies my to screens, however catalyst won't allow my to adjust resolutions on my secondary display. The solution so far is to duplicate my primary display to the secondary. This works fairly well, but it doesn't fill out the screen - not even with 'overscaling'.
This is sad indeed...

Try this:

Open Catalyst > click Graphics at the top left > select Desktops & Displays > right click the icon at the bottom that represents your HDTV and select configure > click HDTV Support tab > select the HD format you need that is compatible for your television.

This should fix your issue, on some tv's you have to force the resolution because the tv doesn't report it correctly to the computer.

Thanks both - now it works - and no offense taken ;-)