I've also completed upgrading RH9 to FC1, on a Dell PowerEdge 2650 server, using FC1 CDs (burnt from ISOs).
I encountered and solved the disk space eror described in http://fedora.artoo.net/faq/#IntelD845 . I used 'linux allowcddma' to solve this problem. FYI, the motherboard chipset is ServerWorks GC-LE chipset and is not listed in the FAQ. Hope the FAQ will add this one.
Here's the steps:
1) boot from FC1 CD1
2) type 'linux allowcddma'
3) follow on-screen instruction
4) when asked, choose to upgrade linux instead of fresh install
5) when asked, choose to update boot loader
6) reboot to FC1
Good luck!
Notes:
1) the Boot GUI (rhgb) is not installed, so the boot process is all text based
2) yum and apt is also not installed. yum is installed when doing fresh install.
3) RH9 2.4.20 kernels are all removed from /boot. My /boot only has fedora's 2.4.22 kernel after the upgrade.