The screen resolution in xorg.conf is set for 800x600 but my actual resolution right now is 1024x768.
tc@box:~$ xrandr
SZ: Pixels Physical Refresh
0 320 x 200 ( 347mm x 260mm ) 0
1 640 x 480 ( 347mm x 260mm ) 0
2 800 x 600 ( 347mm x 260mm ) 0
*3 1024 x 768 ( 347mm x 260mm ) *0
4 1280 x 1024 ( 347mm x 260mm ) 0
5 320 x 400 ( 347mm x 260mm ) 0
6 320 x 240 ( 347mm x 260mm ) 0
7 640 x 400 ( 347mm x 260mm ) 0
8 2048 x 1536 ( 347mm x 260mm ) 0
Here is my current xorg.conf:
# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig: version 304.125 (buildmeister@swio-display-x86-rhel47-08) Mon Dec 1 21:14:12 PST 2014
Section "ServerLayout"
Identifier "Layout0"
Screen 0 "Screen0"
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
EndSection
Section "Files"
EndSection
Section "InputDevice"
# generated from default
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/psaux"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection
Section "InputDevice"
# generated from default
Identifier "Keyboard0"
Driver "kbd"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "Unknown"
ModelName "Unknown"
HorizSync 28.0 - 33.0
VertRefresh 43.0 - 72.0
Option "DPMS"
EndSection
Section "Module"
Load "glx"
EndSection
Section "DRI"
Mode 0666
EndSection
Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Virtual 800 600
Depth 24
Modes "800x600"
EndSubSection
EndSection