You would have to check ATI's site search for you cards drivers in downloads. W7 is probably using a generic native driver that is why it doesn't show the card right? Your using that card if it is the card your monitor cable is plugged into you can also search this site for links to the most recent ATI release i know i've seen the link posted here somewhere. Be sure to create a good restore point prior to updating the driver as well as update it from device manager so you have a driver to roll back to in case it fails.
I used to have an MSI RX9250 video card. It was an ATI card put out by MSI. Though it's the next model newer than yours it's a really outdated card. There are drivers for XP but not for anything later than that. I'm afraid you won't get drivers for that old card.
I tried to get drivers for mine to run on XP x64 Edition. It worked with the drivers that came in the operating systems but ATI wouldn't support anything earlier that the 9500 series. I never got an updated driver for it.
I hate to spread doom and gloom but that's what happened to me.
I had the same problem. Downloaded new drivers from ATI and although it seamed to install, WIN 7 kept the generic driver.
I used Mobility Moder, just google it. Dowload it and used as described in their site. PVT me if u need a link, cause I am not sure i can post it here. They have easy instructions in the site. Basicly you run their free software like a patch in the unpacked ATI driver and then install the driver. It worked fine for me. I also think, as far as I remember, that they explain why this problem is happening on Win 7.