For some reason, my ATI graphics card on my Thinkpad T500 2055-3AG doesn't seem to be detected when Windows automatically installs the two switchable graphics cards. I've tried switching to High Performance Mode, which should activate the card. Unless I uninstall either of them (and TRY to apply Lenovo's own drivers), which unfortunately is a hassle so big that the default situation is the only viable so far. Usually, Windows manages to install its own drivers, before I'm able to do anything at all, but I'm sure that preloads is the only way to go if you don't run into this kind of thing to some extent.
Here, though, it seems that installing the Lenovo drivers is next to impossible.