I have a Athlon 5400+ on an Asus MB with Nvidia chipsets and it works more than well!I have tried, without any luck, installing FC6 on two of my AMD64-based computers.
Try this iso version: http://mirrors.kernel.org/fedora/core/test/6.93/Fedora/x86_64/iso/F-6.93-x86_64-DVD.iso
It's the one i'm using.
Computer #1 is an HP m7640n that is a few months old. It has a dual-core AMD64 X2 5000+ CPU, and an nVidia GeForce 6150 LE display adapter. Computer #2 is one that I assembled, with an AMD64 4200+ CPU, and an nVidia display adapter. This box has FC4 on it, with no new hardware installed since that install. The install (AMD 64-bit version) stops dead after identifying the video card, in both cases. The "X" comes up and that's it. Someone mentioned furnishing parameters when installing on a box with an AMD64 CPU, but I can't seem to locate them. I'm about to pull my hair out, what little there is on top. Any help will be gratefully appreciated. Thanks in advance...Jim