At 04:20 PM 11/6/2002 -0500, you wrote:
>What are the pros and cons of two video cards vs
>one card with dual output such as the Matrox ?

This depends on what the other cards are, and what multi-monitor drivers
and video tools are available for them...if any. I understand that the
Nvidia G4 series has dual monitor support now, and with good 2D, and video
tools. But I have also been told by those who use both, that G4s 2D and
dual monitor drivers are still not as good as Matrox.

I can speak to Matrox cards and drivers.

Right now I am using a  G450 32 meg Dual head on a very high end 22 inch
monitor and a Matrox PCI G200 16 megs on a second average 21 inch monitor.
I started out using just the G450 dual head on two 17 inch monitors. For
this purpose the G450 is the same card as the G550. The G550 just adds some
kind of "video conferenceing " support, that I don't think anybody uses.

With just the G450, when your computer POSTs, and boots, both displays will
show the identical post and boot screens.
Using two cards only the primary display will show the POST and boot screens.

Once on the desktop, the G450 will drive two 17 inch monitors at 1028 X 768
32bit color at 85 Hz no problems. On 21 inch monitors at 1600 X 1200 the
refresh rate drops to 75 Hz and when running a really intensive graphic
type program....like say the XP Serenity screen saver....you will notice a
performance degradation when using the G450 dual head. But with 17 inch
monitors at a lower resolution it works great.

When using two separate video cards, the second head on the G450 can either
be used for an additional SVGA monitor, or for TV out, and or special DVD
features, on your primary monitor.

Using Matrox Powerdesk and two separate video cards, you also have the
advantage of being able to use the Powerdesk utilities separately. For
example, with a single dual head...when you hot key the Zoom feature both
monitors will Zoom. But on a two card system only the monitor where the
cursor is located will Zoom. This is not a big deal for most people. I
rarely run into anybody who uses a lot of the Matrox power tools the way I
do, ... but I prefer this approach.

 From my perspective, what it comes down to is that with two Matrox cards
in the G450 caliber, you will have the advantage of supporting bigger
monitors at higher resolutions without any kind of performance hit, like
you would have with a single G450 dual head.... and you will be able to use
some of the PowerDesk utilities differently, and in my experience for the
better. Note, to fully take advantage of the Matrox PowerDesk  tools, on
all monitors, you need to be using all Matrox Video cards.

However, with 17 inch monitors ( and probably a 19s although I haven't
tried this...ask in the Matrox support forums) The G550 and G450 work great
all by themselves. But when you get up in the 21 inch monitions using a
G450 you will probably want two cards if you desire higher resolutions with
85Hz refresh rates.

Or you can use the new Matrox Parhelia which  has a much much faster
chip,  64 to 128 megs of RAM, and supports 3 monitors. From what I have
read it  easily handles large monitors at very high resolutions and refresh
rates. It also has it's own special tools.

I must say, that in the last few years Matrox has been falling behind the
curve. The company itself appears to be in disarray, having laid off, or
lost a number of it's top engineers. If I were considering an expensive
card, like the Parhelia, I would also take a good long look at the high end
Nvidia G4s that support Dual monitors.  While Parhelia may have the top end
G4s beat in 2D,... when it comes to 3D, Matrox isn't even in the ball game.

Rode
The NOSPIN Group
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