Adding a 3rd monitor - HOW?

I have an SLI motherboard (EPOX EP-9NPAJ+SLI) with 2 PCIX16 slots and a single video card ( Nvidea GEForce 6800 GS - 256MB). I currently run 2 19" monitors from this card. I love the real-estate. I just got another 19" monitor and I want to add this to my PC to stretch the desktop across all 3. The question is how?

I seem to recall that if you wanted to take advantage of the SLI slots that you had to have identical video cards in each. I cannot seem to find another 6800 GS card around plus I lost the crossover chip that came with my motherboard.

Is it possible to just add a PCI display card and run the 3rd monitor from that? If so, does anyone have recommendations?

I don't drive the cards very hard - no games. Mostly code development.

Will I need special code or will XP be able to handle this? I can upgrade to Vista if necessary.

No wonder the avatar's so familiar.

Anyway,
http://www.motherboardpoint.com/t8 [...] nitor.html
http://www.anandtech.com/mb/showdoc.aspx?i=2561

Try these websites. I don't have knowledge in this more-than-one-monitor field.

dead on.

If you use vista i think it works better with 2 cards from the same company. It does not have to be a expensive card either.

You should have a card in one of your PCI-E(X16) slots. just get another budget card(not too cheap, but most cards now will be faster then the 6800GS anyway ) and install it in the other slot, then once its drivers are installed you can just extend your desktop to it from the windows display properties(you will now max out at 4 screens).

SLI is not needed to run multi screen, its only good for games.

XP lets you run ATI and Nvidia card at the same time. Vista is supposed to not like that too much(something with the new driver model).

EDIT.

The avatar is the same person, but a different picture i think(Black and White and zoomed out a bit more). This happens.