Will my SLI motherboard support AMD cards?

If you just need extra monitors then you don’t need SLI (or crossfire, AMD’s version). You can just plug any graphics card you like into any compatible slot, connect your monitor to it and off you go.

SLI is used when you want to use multiple cards to drive the dispaly on one monitor for example to make games play faster (actually thats probably the only reason). For this you need a comptible motherboard and compatible graphics card that are connected together so that they can share data. It’s a pain to set up and usually not worth the bother unless you have a very hi resolution screen.

Well I’ve read that they need to be the same, so i could have these two. I tried a different one and it didn’t work.

Only if you want to connect them together to drive one monitor. If you just want more monitors like more windows desktops you can just add any other card.

If you have a spare PCI slot, sure – it will allow you to hook extra monitors in. I can’t say if it will allow you to do four monitors, though.

AFAIK SLI is PCI-Express only, not regular PCI. Your PCI card will probably not work in the PCI-X slots, but you should have several regular PCI slots available and it will work fine in those. You won’t get SLI from it, but it doesn’t sound as though you need or want SLI.
If you are using the card in conjunction with another PCI card or a PCI-X one then it should Just Work. You might run into some trouble if you are using it with onboard AGP video (but your SLI motherboard is unlikely to have onboard AGP as well) in which case you’d probably need to turn off the AGP in BIOS and use another PCI card.

Correct me if I’m wrong here, but you have 2 different graphics cards, both PCI-E that you want to plug into a SLI compatible motherboard?

With SLI (in your case, Crossfire) you need to not only hook the cards to the motherboard but also together using a SLI bridge. If your cards don’t have compatible bridges or are not SLI/Crossfire compatible anyway what you’re saying won’t work. Putting the 2 cards into the same motherboard and then connecting a monitor to each one won’t work either as Windows is only capable of supporting one card at once unless the cards are connected via SLI/Crossfire. Even though it will probably power both cards you won’t be able to use both, as Windows doesn’t support that. There is a very good chance I’m wrong there, but please, correct me.

Also, for crossfire/SLI I believe you do need 2 identical cards so I wouldn’t bother trying to acquire a bridge if your two cards are different.

@DeanV I have successfully run two monitors from two separate video cards in both Windows 2000 and in Linux. As you might guess it was a long time ago that I did it, so it may or may not still be possible.

@DeanV SLI has 2 (or more) cards running 1 monitor. Windows can display multiple desktops on multiple monitors from multiple cards. Also the graphics cards do not need to be identical (other than being the same make and generation). Hybrid SLI where you have a low power card to run your day to day stuff and a high power card that kicks when you load a game is an increasingly common strategy to save power in laptops.

@DeanV Well there were two identical cards from that motherboard, so those must work, but they arent AMD graphics or HIS as far as i know.I tired plugging in the second, different card, but nothing showed up on the motherboard. Is it a setting in the bios to enable two video cards?

The other cards that msut have been in it have no SLI connectors, they are just identical. Basically all I want to know is if I did something wrong where the second card didn’t work, or if they need to be the same.

Well, I tried two different cards in the motherboard and it crashed something, and windows had to repair itself. Is there something I did wrong, or will it just not work with different ones?