2 nVidia cards, 3 monitor question

[amaghazi]

Hey guys,
I am running a 2nVidia 7950GX2 cards with a 3 monitor system on a DELL XPS 720 desktop on Windows 7.
latest nVidia driver is installed (10/10/2012)

Each card has 2 DVIs (4 DVIs total). Both cards are on SLI bridge. SLI is disabled on the software.
I would like to run one main monitor on one card, and 2 side monitors on the other card. Desktop will be extended on all 3.
However, PC only recognizes monitor or 2 monitors attached to the main card only.
Both cards work fine.
However, for some reason only the one or two monitors attached to the main card (i do not know how the computer determines the main card) are detected and recognized.
When I interchange the cards, same thing happens: the card on that specific slot is considered main and monitors attached to it are detected. Monitors attached to the other card are not detected.

I tried removing the SLI bridge, nothing happens. I tried both through windows and nVidia control panel, but same result. Only monitors attached to one card are recognized.

Could someone please help me find a solution for this problem?

more info: I used to run this configuration on Windows XP with no problem. But for some reason I cannot do it on Windows 7

 

[Swolern]

Why is SLI disabled? You need it enabled to activate 3 monitors.

 

[amaghazi]

I tried it both ways.
It is weird.
Windows 7 can sense that there is a monitor but does not display anything on it.
It is a software problem but i dont know what to do about it

 

[Derza10]

In SLI don't you have to connect all the monitors to the main card? I could be wrong.

 

[amaghazi]

Yes I have 2 cards. each has 2 DVIs
When I run SLI or not SLI it does not make a difference for me.
So when I connect 2 monitors to the main card they work fine either way.
My issue is that I want to run a 3rd monitor on the other card but i cant.
I used to be able to do it with no SLI in windows XP. now i cant.

 

[amaghazi]

so the configuration would be one monitor on one card and two monitors on another card and I cannot get that to work.

 

[whooleo]

Is SLI enabled in driver panel? Make sure SLI bridge is connected.

 

[amaghazi]

When your SLI is on you cannot drive multiple monitors.
SLI makes 2 cards as one.

 

[Swolern]

Yes I have 2 cards. each has 2 DVIs
When I run SLI or not SLI it does not make a difference for me.
So when I connect 2 monitors to the main card they work fine either way.
My issue is that I want to run a 3rd monitor on the other card but i cant.
I used to be able to do it with no SLI in windows XP. now i cant.

Are all 3 monitors the same?
Can you get 2 monitors working with 1 monitor on each card with SLI enabled?