Prev | Current Page 110 | Next

Chris Tyler

"X Power Tools"

5??“90.0 while the projector supports 28.0??“84.0, use
31.5??“84.0 in your config file.
If you cannot find documentation for your monitor and must calculate a frequency
range, be conservative! Here is a quick-and-dirty formula that lets you calculate an
approximate horizontal frequency, generally within 1 kHz:
HorizSync = VertRefresh * (VerticalResolution + 40) / 1000
In this formula, VerticalResolution is the height of the selected resolution, in pixels.
What??™s the 40 doing in there? Well, it provides some time for the vertical retrace,
when the CRT beam is repositioned from the bottom to the top of the display.
This formula does not work for double-scan and interlaced modes.
It??™s important not to restrict the X server too tightly. If you want to use a VertRefresh
rate of exactly 60.0, you may find that no modes are available that exactly match that
frequency, and the X server will be unable to start. But, if you relax the range by just
1 Hz to 59.0??“61.0, the server is much more likely to find a workable configuration
(Section 3.15).
Let??™s suppose that you have a monitor for which you don??™t have any documentation
??”but you??™re fairly confident that it can support a resolution 1024 ?— 768 at a 75
Hz refresh rate, and you want to use it at only that resolution.


Pages:
98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122