 DualHead2Go technology brief
Innovative Matrox product divides 1 monitor output into
2
Matrox DualHead2Go provides a completely new
way to add multi-display support to a laptop or desktop computer. This external
box connects to the standard monitor connector of a computer and divides the
signal for use with 2 separate monitors. Each display can then be used to view
different information. There are devices from other manufacturers that
also "divide" the monitor output from a computer for 2 or more monitors, but
they only serve to copy the same output.
Traditionally, multi-display
support is added to a system by adding a new graphics card. Matrox is an
industry leader in multi-display technology and most of its graphics cards
include multi-display support. However, unlike with a new graphics card,
DualHead2Go doesn't require opening a computer, inserting parts into it,
or replacing any hardware or software. This solution uses the existing hardware
and software of a system for 2D, 3D, and video acceleration.
Think outside the box
DualHead2Go
receives input from the regular monitor connector of a computer, but it also
transmits information through this connection. This is done using EDID
(Extended Display Identification Data), a standard data format used by computer
monitors to inform a system of their capabilities. Included in this data is
information on supported display resolutions. Resolution is measured in the
number of horizontal by vertical pixels (the smallest display units) displayed
at a time. DualHead2Go reports to the system that it's capable of
standard resolutions (800 x 600, 1024 x 768, and 1280 x 1024) as well as
resolutions that are effectively twice as wide as standard resolutions (2048 x
768 and 2560 x 1024).
When you first restart a computer after
connecting DualHead2Go to it, the Windows operating system detects a
single new "monitor" and its settings. If this new "monitor" isn't the only one
in the system (as with a laptop), it may need to first be enabled in Windows.
You can check display settings in Windows by right-clicking the Windows desktop
background and then clicking Properties > Settings. Here, you can
select the number of the display you're using and make sure " Extend my
Windows desktop onto this monitor" is enabled for that display. You can
also change the resolution by moving the Screen resolution (Windows XP)
or Screen area (Windows 2000) slider.
After the
DualHead2Go "monitor" is first enabled, that display will use a
standard, single-display resolution (800 x 600). Since this resolution doesn't
have enough information to divide over 2 displays, DualHead2Go defaults
to displaying the same information on both monitors.
However, the more
typical usage for this product occurs when one of the available wide-screen
resolutions (2048 x 768 or 2560 x 1024) is applied. With a wide-screen
resolution, Windows continues to treat the monitor output as a single display
(for example, for the purposes of selecting color settings), but
DualHead2Go automatically divides the display image in half for use with
2 separate monitors (1024 x 768 or 1280 x 1024 on each display). One physical
monitor shows the left half of this Windows "monitor" and the other shows the
right half.
 |
|
This Windows XP settings dialog box shows
an example configuration with a laptop using DualHead2Go. In this case, display
"1" is the built-in display of the laptop while display "2" is connected to
DualHead2Go and is treated by Windows like a single display twice as
wide as a typical display. DualHead2Go automatically divides display "2"
into 2 separate displays, effectively providing this system with 3 displays at
time. |
From the operating system point of view, the
multi-display provided by DualHead2Go is similar to the "stretched" mode
available with Matrox multi-display graphics cards. If there are no other
displays in the system, one of the advantages with this mode is that software
doesn't need to be multi-display aware. For example, 2D, 3D, and video
acceleration can occur as if the 2 displays were 1 (albeit, 1 display with a
resolution twice as wide as a typical display).
You can use the
multi-display support provided by DualHead2Go without adding or
replacing any system software. The display driver of the existing graphics
hardware can continue to be used (provided it supports a 2048 x 768 or 2560 x
1024 resolution). However, to improve multi-display support, DualHead2Go
includes Matrox PowerDesk software. This software has the same easy-to-use
interface included with Matrox graphics cards. Among other things, PowerDesk
provides controls for where dialog boxes and message boxes appear, how windows
are maximized, and adjusting image quality. PowerDesk software helps improve
image quality by calibrating the phase adjustment to properly interpret the
analog input signal.
Inside the black
box
The existing graphics hardware and software in the computer
does nothing different other than providing a monitor signal with a resolution
that's twice as wide as a standard resolution. The computer continues to use
its own graphics processor to render a single display to its graphics memory.
The real "magic" of making 1 display into 2 occurs inside the
DualHead2Go box.
In DualHead2Go, the monitor signal from the
computer is first converted to digital data using various techniques to ensure
the best possible conversion. These techniques include gain compensation to
normalize the signal and phase adjustment to properly interpret the analog
input signal.
After the input is converted to digital data,
DualHead2Go uses Matrox patent-pending technology to divide the display
information into 2 display outputs. These signals are then converted into an
analog signal using 2 DAC (digital-to-analog) converters and passed through the
2 standard analog (HD-15) monitor connectors at the back of the
DualHead2Go box. Throughout the process, no pixels are added, dropped,
scaled, or otherwise changed. DualHead2Go preserves all the on-screen
information provided by the original monitor signal.
Conclusion |
|
 |
The DualHead2Go upgrade provides a unique and
easy way to add multi-display capability to a system. This product simply
connects to the external monitor connector of a computer – there are no
parts to insert in a computer and no hardware or software is replaced. This
product adds support for an extra display while leveraging the performance of
your existing graphics hardware. The extra display allows more information at a
time to be viewed and this can lead to improvements in productivity and help
reduce errors. |
|
