[CentOS] Centos 5 -- X default resolution

Install did not recognize my LCD monitor, probably due to the old KVM.  
Anyway, I went to config monitor after install (logged in as root) and 
selected the monitor in my NOC where this box is going to live anyway.  
I then had to exit X and restart it for this selection to take.

It this point the resolution was 1280x1024 which was unreadable.  I 
changed it to 1024x768 which works well.

However at bootup and for the login screen the resolution is still 
1280x1024.  How do I change this?