I am having a strange issue with my laptop (a Dell XPS 1645). I needed to reformat and do a clean install of win 7 ultimate 64bit, and reinstall the ATI drivers that came from Dell's website (the same ones it had before the wipe). It's own LCD panel failed (a common defect in this model) so it stays plugged into a external monitor that has an native resolution of 1920x1200 (16:10 ratio). But due to the low power of this GPU I run most games at 1280x800 which had worked fine before the wipe. Now all of a sudden setting a 1280x800 resolution anywhere, Be it in a game or even at the desktop causes the monitor to letter box with a distorted image (big black bars top and bottom and a compressed image).. What makes this stranger is when the system is set to 1280x800 the monitor's information display shows it's receiving 1280x960 instead, and I assume not being a 16:10 ratio is what's causing the distortion. There is no issues with setting 1680x1050 or its native 1920x1200 though some games have run poorly when set that high. So I am a bit stumped here. And as I said this exact same setup worked fine before the system wipe.
Now after testing it on other monitors it is the same, Setting 1280x800 outputs 1280x960 instead...

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