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>13. Overdriving Your Monitor</H1
><P
>You should absolutely <EM
>not</EM
> try exceeding your
monitor's scan rates if it's a fixed-frequency type. You can smoke
your hardware doing this! There are potentially subtler problems with
overdriving a multisync monitor which you should be aware of.</P
><P
>Having a pixel clock higher than the monitor's maximum bandwidth is
rather harmless, in contrast. It's exceeding the rated maximum sync
frequencies that's problematic. Some modern monitors might have
protection circuitry that shuts the monitor down at dangerous scan
rates, but don't rely on it. In particular there are older multisync
monitors (like the Multisync II) which use just one horizontal
transformer. These monitors will not have much protection against
overdriving them. While you necessarily have high voltage regulation
circuitry (which can be absent in fixed frequency monitors), it will
not necessarily cover every conceivable frequency range, especially in
cheaper models. This not only implies more wear on the circuitry, it
can also cause the screen phosphors to age faster, and cause more than
the specified radiation (including X-rays) to be emitted from the
monitor.</P
><P
>However, the basic problematic magnitude in question here is the slew
rate (the steepness of the video signals) of the video output drivers,
and that is usually independent of the actual pixel frequency, but
(if your board manufacturer cares about such problems) related
to the maximum pixel frequency of the board.</P
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>So be careful out there...</P
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