288 lines
5.1 KiB
HTML
288 lines
5.1 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>Questions and Answers</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="X.org/XFree86 Video Timings HOWTO"
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HREF="index.html"><LINK
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REL="PREVIOUS"
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TITLE="Using Interlaced Modes"
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HREF="inter.html"><LINK
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REL="NEXT"
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TITLE="Fixing Problems with the Image."
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HREF="fixes.html"></HEAD
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><BODY
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CLASS="sect1"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>X.org/XFree86 Video Timings HOWTO</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="inter.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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></TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="fixes.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="sect1"
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><H1
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CLASS="sect1"
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><A
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NAME="answe"
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></A
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>15. Questions and Answers</H1
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><DIV
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CLASS="qandaset"
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><DL
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><DT
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>Q: <A
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HREF="answe.html#AEN406"
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>The example you gave is not a standard screen size, can I use it?</A
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></DT
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><DT
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>Q: <A
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HREF="answe.html#AEN411"
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>It this the only resolution given the 65Mhz dot clock and 55Khz
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HSF?</A
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></DT
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><DT
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>Q: <A
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HREF="answe.html#AEN418"
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>You just mentioned two standard resolutions. In Xconfig, there are
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many standard resolutions available, can you tell me whether there's
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any point in tinkering with timings?</A
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></DT
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><DT
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>Q: <A
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HREF="answe.html#AEN423"
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>Can you summarize what we have discussed so far?</A
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></DT
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></DL
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><DIV
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CLASS="qandaentry"
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><DIV
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CLASS="question"
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><P
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><A
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NAME="AEN406"
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></A
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><B
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>Q: </B
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>The example you gave is not a standard screen size, can I use it?</P
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></DIV
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><DIV
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CLASS="answer"
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><P
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><B
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>A: </B
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>Why not? There is NO reason whatsover why you have to use 640x480,
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800x600, or even 1024x768. The X server lets you configure your hardware
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with a lot of freedom. It usually takes two to three tries to come up the
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right one. The important thing to shoot for is high refresh rate with
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reasonable viewing area. not high resolution at the price of eye-tearing
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flicker!</P
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></DIV
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></DIV
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><DIV
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CLASS="qandaentry"
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><DIV
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CLASS="question"
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><P
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><A
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NAME="AEN411"
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></A
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><B
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>Q: </B
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>It this the only resolution given the 65Mhz dot clock and 55Khz
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HSF?</P
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></DIV
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><DIV
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CLASS="answer"
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><P
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><B
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>A: </B
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>Absolutely not! You are encouraged to follow the general
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procedure and do some trial-and-error to come up a setting that's
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really to your liking. Experimenting with this can be lots of fun.
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Most settings may just give you nasty video hash, but in practice a
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modern multi-sync monitor is usually not damaged easily. Be sure
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though, that your monitor can support the frame rates of your mode
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before using it for longer times.</P
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><P
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>Beware fixed-frequency monitors! This kind of hacking around can
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damage them rather quickly. Be sure you use valid refresh rates for
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<EM
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>every</EM
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> experiment on them.</P
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></DIV
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></DIV
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><DIV
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CLASS="qandaentry"
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><DIV
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CLASS="question"
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><P
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><A
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NAME="AEN418"
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></A
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><B
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>Q: </B
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>You just mentioned two standard resolutions. In Xconfig, there are
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many standard resolutions available, can you tell me whether there's
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any point in tinkering with timings?</P
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></DIV
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><DIV
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CLASS="answer"
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><P
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><B
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>A: </B
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>Absolutely! Take, for example, the "standard" 640x480 listed in
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the current Xconfig. It employes 25Mhz driving frequency, frame
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lengths are 800 and 525 => refresh rate ~ 59.5Hz. Not too bad. But
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28Mhz is a commonly available driving frequency from many SVGA boards.
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If we use it to drive 640x480, following the procedure we discussed
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above, you would get frame lengths like 812 (round down to 808) and
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505. Now the refresh rate is raised to 68Hz, a quite significant
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improvement over the standard one.</P
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></DIV
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></DIV
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><DIV
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CLASS="qandaentry"
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><DIV
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CLASS="question"
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><P
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><A
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NAME="AEN423"
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></A
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><B
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>Q: </B
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>Can you summarize what we have discussed so far?</P
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></DIV
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><DIV
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CLASS="answer"
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><P
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><B
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>A: </B
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>In a nutshell:</P
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><P
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></P
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><UL
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><LI
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><P
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> for any fixed driving frequency, raising max resolution incurs the penalty
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of lowering refresh rate and thus introducing more
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flicker.</P
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></LI
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><LI
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><P
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> if high resolution is desirable and your monitor supports it, try to
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get a SVGA card that provides a matching dot clock or DCF. The higher,
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the better!</P
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></LI
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></UL
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></DIV
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></DIV
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></DIV
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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SUMMARY="Footer navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TD
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WIDTH="33%"
|
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ALIGN="left"
|
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VALIGN="top"
|
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><A
|
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HREF="inter.html"
|
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ACCESSKEY="P"
|
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>Prev</A
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></TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
|
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><A
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HREF="index.html"
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ACCESSKEY="H"
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>Home</A
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></TD
|
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><TD
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WIDTH="33%"
|
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ALIGN="right"
|
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VALIGN="top"
|
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><A
|
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HREF="fixes.html"
|
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ACCESSKEY="N"
|
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>Next</A
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></TD
|
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></TR
|
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><TR
|
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><TD
|
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WIDTH="33%"
|
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ALIGN="left"
|
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VALIGN="top"
|
|
>Using Interlaced Modes</TD
|
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><TD
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WIDTH="34%"
|
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ALIGN="center"
|
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VALIGN="top"
|
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> </TD
|
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><TD
|
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WIDTH="33%"
|
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ALIGN="right"
|
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VALIGN="top"
|
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>Fixing Problems with the Image.</TD
|
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></TR
|
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></TABLE
|
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></DIV
|
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></BODY
|
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></HTML
|
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> |