Yesterday I messed up badly with GNOME configuration. My R & D result into an error on the first console that read as follows:
INIT: Id respawning too fast: disabled for 5 minutes
GNOME was broken badly. Screen was just flicked several times. To fix this problem:
a) Reboot Fedora Core Linux box
b) Boot into single user mode (or text mode i.e. mode init 3 will also do the job,IMPO)
c) Type the following command to fix Display card related stuff:
# redhat-config-xfree86 --reconfig
Above command allows you to fix all problems or allows reconfiguring X windows system.