[CentOS] Can't get resolution higher than 1280x1024 - Centos 5

Wed May 2 18:00:53 UTC 2007
Alfred von Campe <alfred at von-campe.com>

I have a similar problem as the OP.  I'm trying to configure a Dell  
2407WFPb LCD monitor at its native resolution of 1920x1200 on CentOS  
4.4 system.  But I could only get to 1600x1200 in system-config- 
display.  If I manually edit the xorg.conf file to include 1920x1200  
and restart the X server, that resolution disappears from the  
xorg.conf file.

CentOS doesn't know about the 2407WFPb; the closest is the 2405FPW,  
so I manually set it to use this.  Looking at the specs for these two  
monitors, they seem to have the exact same horizontal and vertical  
frequencies for 1920x1200 (74.0 kHz and 60.0 MHz), which are in the  
range specified in xorg.conf.

I've also tried to set the monitor to "Generic 1920x1200 LCD), but I  
still don't get that mode as an option.  I am offered 1920x1440, but  
I don't think the monitor can support that.  BTW, I am using the DVI  
output of an NVIDIA GeForce 6200 card, and I am running the closed  
source NVIDIA driver.

Any thoughts on what I can try next to support the native 1920x1200