I recently upgraded laptops, it has a dedicated AMD/ATI graphics card as well as an Integrated HD graphics adapter. After getting it all setup I tried to work on a Windows Phone app. Everything went fine but when I started the app on the emulator after the initial “Windows Phone” … “Loading” screen, the screen went blank as shown below
After putting this out to a mailing list I’m on I received good feedback from Rob Miles and Den Delimarsky that the issue might be this sort of dual graphics adapter configuration.
After a little bit of searching, I found a mechanism within the Catalyst Control Center where I could assign different modes to different applications.
So after finding XdeLauncher.exe at C:\Program Files (x86)\Microsoft SDKs\Windows Phone\v7.1\Tools\XDE Launcher I configured it to use the Power Saving graphics processor and life is good again (i.e. my emulator works great! 
-twb
