Monitor settings during install good; After install bad

[Dwight A]

What are the monitor settings during installation of Fedora Core (in 
general)?

Specifically, I've tried FC2 and FC3 for x86_64 and although my video card 
is detected correctly as ATI Radeon 9200SE while my monitor is not detected 
(reported as "Unknown monitor"), the video screen during installation is 
fine.  The installation appears to use X Windows successfully.  Is it really 
using X Windows during install?

During post-install, I've set the monitor to Generic CRT 1024x768, Millions 
of colors, which I would expect from my MaxTech XT-5888; but upon reboot and 
after grub, the screen is corrupted such that I cannot read anything on the 
screen.

I also reinstalled and kept the default monitor settings as 800x600, 
Millions of colors, and also had a corrupt screen.

If I could use the monitor settings that are used during install, I assume 
my screen would not be corrupt.  What are the monitor settings during 
install and how can I use them after install?

Regards,
Dwight