ATI HDTV Adapter -- Can I resize the 640x480 resolution so there is no overscan?

I have an ATI Radeon 9700 Pro and the official ATI HDTV dongle. When I try to use 640x480 I have a significant amount of overscan and can only barely see the taskbar... (lots of games are unplayable because I can't see the bottom of the screen)


However, if I use 640x432 everything fits perfectly. The only problem is that no games support 640x432, they only support 640x480.


So, I'm wondering if I can somehow resize my screen in the drivers so that 640x480 doesn't overscan. Is this possible?