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Optimising performance – IBM G41/G50 User Manual

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Optimising performance

"Plug and Play"

Monitor implementation of the VESA DDC standard offers
the capability of automatic optimisation of monitor
performance (“Plug and Play”). In order for automatic
optimisation to be effective, the attaching computer must
also be hardware and software enabled for DDC
operation.

The monitor sends data to the computer. The computer
stores the received data, and determines the display
mode that best uses the capabilities of the monitor
through analysis of this data.

Display Modes

The computer uses software to control the way in which
the image is displayed on the screen. This software is
supplied as part of your computer operating system (e.g.
DOS, OS/2). If a video adapter card is installed, additional
software would have been supplied with it.

The way in which the image is displayed on the monitor
screen is called the

Display Mode and it is governed by

two main factors, the

Addressability and the Refresh

Rate.

Addressability is the number of horizontal and vertical
picture elements (pels) that form the screen image, e.g.
800 x 600.
Refresh Rate is the number of times per second that the
screen image is “repainted” by the computer or video
adapter card, e.g. 72 Hz.

Display Modes can be either “Interlaced” or “Non-
interlaced” (see

Glossary).

Your monitor can support a wide range of display modes.
For the display modes in Table 1, the screen image has
been optimised during manufacture.

Selecting display modes

The display mode that your monitor uses is controlled by
the computer. After the computer and the monitor have
been turned on, the computer will select a display mode.
You may want to use a different display mode, one that
produces the best possible screen image for your
application.

Ensuring flicker-free operation

If your computer is hardware and software enabled for
DDC operation, it will automatically select the highest
refresh rate that your monitor and computer support for
your selected display mode. If DDC is not enabled,
consult your software operating system manual to
determine what display modes it can support. Using the
necessary software utilities or graphics adapter card,
select the highest (non-interlaced) refresh rate both the
computer and the monitor can support (generally 72 Hz or
higher). Note that the monitor is capable of flicker-free
operation at addressabilities up to 1024 x 768.

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