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<HTML>
<HEAD>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
<META NAME="Author" CONTENT="Joshua Neal">
<META NAME="Description" CONTENT="Pure VGA/SVGA hardware programming (registers, identification, and otherlow-level stuff.)">
<META NAME="KeyWords" CONTENT="VGA SVGA hardware video programming">
<TITLE>FreeVGA - Product Recommendations for Video Developers</TITLE>
</HEAD>
<BODY>
<CENTER><A HREF="home.htm">Home</A> <A HREF="#intro">Introduction</A> <A HREF="#monitors">Recommended</A>
<A HREF="#failures">Failed</A> <A HREF="#test">Test</A> <A HREF="home.htm#product">Back</A>&nbsp;
<HR WIDTH="100%"><B>Hardware Level VGA and SVGA Video Programming Information
Page</B></CENTER>
<CENTER>Product Recommendations for Video Developers&nbsp;
<HR WIDTH="100%"></CENTER>
<A NAME="intro"></A><B>Introduction</B>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; This page is to provide
hardware recommendations for those implementing the information on this
site.&nbsp; There are no recommendations for video cards, as the goal is
to increase programmer support for all cards, existing or otherwise, rather
than try to influence people to buy a specific video card implementation.&nbsp;
I will, however recommend hardware, other than the video cards themselves
that are helpful in the development of software for video cards in general.
Monitors are a strong issue to me, both for safety concerns, and financial
concerns, as it is usually advantageous to buy an new, indestructable monitor
than to burn through many cheap, expendable monitors.
<P><B>&nbsp;<A NAME="monitors"></A>Monitors Recommended</B>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; For a monitor to be recommended
it must meet all of the following criteria:
<UL>
<LI>
It should be able to tolerate improperly formed video inputs for an extended
period of time without the possibility of being damaged.&nbsp; It should
also be tolerant to extremely frequent mode changes.&nbsp; Damage due to
this kind of operation should not be excluded by the standard manufacturer's
warranty.&nbsp; This is critical due to the replacement cost of high-performance
monitors, and due to the possible safety and fire hazards failing monitors
may cause.</LI>
<LI>
It should be able to synchronize to a wide variety of properly formed signals,
including both standard and custom video timings.&nbsp; This important
for developing the modes required for special applications.</LI>
<LI>
It should handle the maximum frequencies/resolutions that can be generated
by current and future (to a reasonable extent) video chipsets.</LI>
<LI>
It should be compliant to all levels of display to host communication and
power mamagement so code can be developed that implements these features
of the video hardware.</LI>
<LI>
If the monitor allows the picture controls to be saved/restored on changes
in mode, it should be allowed to defeat this feature so that the generated
video timings can be adjusted to minimize the visible effects of mode change.</LI>
<LI>
It should be currently available on the market and covered by manufacturers
warranty for the period of time required to develop the desired application.</LI>
<LI>
It has been put through my own personal monitor torture tests, as well
as operated for an extended period of time under conditions related to
video software development.</LI>
</UL>
The following monitors have been evaluated by myself personally, and have
been determined to meet all these criteria.
<UL>
<LI>
At this time, there are no monitors that I have determined meet all these
criteria.</LI>
</UL>
<A NAME="failures"></A><B>Monitor Failures</B>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; This section lists monitors
that have either died for me while testing, or have died for others in
a fashion that would imply that the programmer was responsible for their
failure.&nbsp; This does not imply that the programmer was at fault, as
these things naturally happen when developing drivers.&nbsp; I strongly
recommend the purchase of one of the recommended monitors, to avoid damaging
a valuable monitor
<P><B>Compaq VGA (not SVGA)</B> -- I do not know the model specifically.&nbsp;
It was a fixed frequency model, and the horizontal circuitry was damaged.&nbsp;
The problem was repeatable after repairs were made, so I believe that the
monitor can be damaged by normal mode testing. I have met others who claim
to have experienced this same problem.&nbsp; Not recommended.
<P><B>CTX CMS-1561LR</B> -- The problem with this monitor occured when
driving the monitor at the high end of its frequency envelope.&nbsp; The
monitor synced to the frequency, but may have been slightly overdriven.&nbsp;
The horizontal output transistor and some capacitors were replaced and
the monitor was restored to working order.&nbsp; The problem has not been
repeated, so ordinary failure is likely.
<P><B>NCR MBR 2321</B> -- This one comes from a friend in Fayetteville,
AR, whose monitor blew caps while writing a svgalib video driver.&nbsp;
The explosion from the capacitors shattered the rear of the picture tube,
damaging the monitor beyond repair.&nbsp; Not recommended due to the catastrophic
nature of the failure.&nbsp; The operation being performed when the failure
occurred was frequent mode changing.
<P><A NAME="test"></A><B>Test Equipment Recommended</B>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; There are certain pieces
of test equipment that can come in handy when working with video cards.&nbsp;
This can be especially important when verifying that the video signal being
generated is, in fact the one intended by the programmer.&nbsp; Failure
to do this can cause catastrophic failure when the driver is used in conjunction
with a fixed-frequency or other monitor that can be damaged by improper
inputs.
<UL>
<LI>
At this time, I cannot recommend any test equipment other than a good frequency
counter, as this is really not in my area of expertise.&nbsp; If you can
help me in my research into this, I would be greatly appreciative.</LI>
</UL>
Notice: All trademarks used or referred to on this page are the property
of their respective owners.
<BR>All pages are Copyright &copy; 1997, 1998, J. D. Neal, except where
noted. Permission for utilization and distribution is subject to the terms
of the <A HREF="license.htm">FreeVGA Project Copyright License</A>.&nbsp;<IMG SRC="http://www.goodnet.com/~tinara/cgi-bin/imgserv.cgi?logo3.gif" >
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