The Intel driver uses the bios to determine resolutions, you need to use an app to change the bios
resolution if you want 1920x1200. The default is 1920x1400, which won't display properly. You'll also need a 1920x1200 modeline, I've included it at the bottom of the post.
Install the RPM and run 855resolution.
RPMS: i386 SRPM
[root@host ~]# 855resolution -l
855resolution version 0.4, by Alain Poirier
Chipset: Unknown (id=0x27708086)
VBIOS type: 2
VBIOS Version: 1215
Mode 30 : 640x480, 8 bits/pixel
Mode 32 : 800x600, 8 bits/pixel
Mode 34 : 1024x768, 8 bits/pixel
Mode 38 : 1280x1024, 8 bits/pixel
Mode 3a : 1600x1200, 8 bits/pixel
Mode 3c : 1920x1400, 8 bits/pixel
Mode 41 : 640x480, 16 bits/pixel
Mode 43 : 800x600, 16 bits/pixel
Mode 45 : 1024x768, 16 bits/pixelMODE=5c
X=1920
Y=1200
Mode 49 : 1280x1024, 16 bits/pixel
Mode 4b : 1600x1200, 16 bits/pixel
Mode 4d : 1920x1400, 16 bits/pixel
Mode 50 : 640x480, 32 bits/pixel
Mode 52 : 800x600, 32 bits/pixel
Mode 54 : 1024x768, 32 bits/pixel
Mode 58 : 1280x1024, 32 bits/pixel
Mode 5a : 1600x1200, 32 bits/pixel
Mode 5c : 1920x1400, 32 bits/pixel
Change the resolution:
[root@host ~]# 855resolution 5c 1920 1200
855resolution version 0.4, by Alain Poirier
Chipset: Unknown (id=0x27708086)
VBIOS type: 2
VBIOS Version: 1215
** Patch mode 5c to resolution 1920x1200 complete
I've also included an init.d script to change the setting at boot, just edit /etc/sysconfig/855resolution:
MODE=5c
X=1920
Y=1200
RPMS: i386 SRPM
My xorg.conf Display section
Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "LCD Panel 1920x1200"
HorizSync 30 - 70
VertRefresh 60
ModeLine "1920x1200" 162.0 1920 1984 2176 2480 1200 1201 1204 1250
+hsync +vsync
Option "dpms"
EndSection
