Monitor Configuration
Please enter your monitor specs. If you don't know one of these, leave it blank. This information is used to generate warnings if the requested mode is outside your monitor's capabilities. These values are not required.
Horizontal Sync Rate
The number of scan lines (visible and invisible) that are drawn on the screen per second.
kHz min kHz max
Refresh Rate
Also known as the Vertical Sync Rate, this is the number of screen refreshes per second.
Hz min Hz max
Dot Clock Frequency
Also known as the Pixel Clock, this is the speed at which pixels are drawn on the screen.
MHz maximum

Basic Configuration
For the best Refresh Rate, fill in all fields except Refresh Rate. For maximum resolution, set both Horizontal and Vertical Resolution to zero.
Visible Resolution
This setting determines how many pixels will be visible onscreen. If both horizontal and vertical resolution are zero, the maximum possible resolution given the Refresh Rate, Dot Clock, and Aspect Ratio will be used.
xpixels
Refresh Rate
Also known as the Vertical Sync Rate, this is the number of screen refreshes per second. Low values may cause a flickering effect, while higher values produce a more stable display.
Hz (actually 0)
Dot Clock Frequency
Also known as the Pixel Clock, this is the speed at which pixels are drawn on the screen.
MHz

Constrain Aspect Ratio
Constrains the visible resolution to a given aspect ratio. The typical CRT ratio is 4/3.
/
Interlace
Interlace draws only half of the screen each refresh, doubling the effective refresh rate. Interlaced modes are well known for their high flicker, but a 60Hz interlaced mode looks much better than a 30Hz non-interlaced mode.
interlace
Doublescan
Doublescan draws every line on the screen twice, doubling the effective dot clock and allowing lower resolutions. This is often necessary for modes like 320x200.
doublescan

Advanced Configuration
Do not change the following sync times unless you know what you're doing. These almost never need changing.
Horizontal Sync Time
This should vary from 3.5 to 4.0, with 3.8 being a fairly safe bet.
microseconds
Vertical Sync Time
This should vary from 50 to 300, with 150 being a fairly safe bet.
microseconds


xtiming-3.3.0
Designed and written by Ethan Fischer.
This script would not have been possible without the XFree86 Video Timings HOWTO.