The driver you're going to need for Windows 8 is going to be different than the driver needed for XP. I don't see any reason to attempt to install the XP driver if it's giving you issues. Move onto your Windows 8 install and update with the Windows 8 driver available from AMD.com.
I'm unable to Install Windows 8 because the screen resolution is incorrect and I am unable to see the Windows 8.
If I were to install Windows 8 on another computer and then make a disc and insert it into this one, would I be able to install Windows 8 booting from the disc with a res. higher than 640x480?