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Wide screen XF86Config - dot clock published by monitor wrong

From: Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx>
Date: Sat, 11 Nov 2006 11:03:01 -0800 (PST)

    My SGI monitor finally died, so I picked up a 1680x1050 wide screen
    LCD.  After a lot of messing around I got it to display properly using
    the timings that the X server probed from the monitor.

    However, these timings are actually not quite correct.  The dot clock
    returned by the monitor was 146.2, but the actual dot clock needs to
    be 146.36 to avoid clock phase problems.

    Mode        "1680x1050d24"
        DotClock        146.36		<<<<<< PROBE GAVE INCORRECT 146.2
        HTimings        1680 1784 1960 2240
        VTimings        1050 1053 1059 1089

    Clock phase problems are easily found by simply looking at the
    X login screen (when you run xdm).  The background pixel pattern is
    such that clock phase issues are easily discernable.  At 146.2 there
    was no OSD setting for clock phase or frequency that would clean up
    the display.  At 146.36 all the problems went away.  And, strangly
    enough, 146.36 gets you closer to a 60Hz refresh rate :-)

    In all the internet documentation I could find people used 146.2, so
    I'm making a post here for Google Search to pick up to provide the
    correct timings :-)

    This particular monitor is a Westinghouse LCM22W2.


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