When trying to use the graphical installer on a computer with ATI Rage 128 video card it attempts to use ATI Mach64 server. This server doesn't support this card. Installer fails without giving a chance to switch to generic SVGA server.
This issue has been assigned to a developer for further action.
This card is not supported in release 6.1. Check out the xfree86.org site for more information about the support for that card.