From
Section "ServerLayout" delete
Screen 1 "Screen1" RightOf "Screen0"
Delete this section:
Code:
Section "Monitor"
Identifier "Monitor1"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
EndSection
And delete the last section:
Code:
Section "Screen"
Identifier "Screen1"
Device "Card1"
Monitor "Monitor1"
SubSection "Display"
Viewport 0 0
Depth 1
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 4
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 8
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 15
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 16
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 24
EndSubSection
EndSection
Then retry starting X.