On motherboards with 2 PCI-E x16 slots...

[castleking]

I have a need for a multimonitor setup with three monitors. I will be using Vista unfortunately (don't bother asking why), so I would like to avoid using integrated graphics. I was going to build a core 2 system on a p965 mobo. I won't overclock this system, as it won't be doign much system intensive things like games. I was thinking about this mobo http://www.newegg.com/Product/Product.asp?Item=N82E16813135022. Its cheap (which I like) and it has two x16 slots. I suppose my quetion boils down to this: can I use two video cards in a crossfire mobo that won't be crossfired? also, can they be different video cards?

 

[akhilles]

You mean running 2 nvidia cards in sli on Crossfire mobo? Yes, but there's no guarrante. & there may be a performance hit. Why bother? Just get a intel SLI mobo.

ECS NFORCE 570 SLIT-A (a member uses this mobo in the forum. he can tell you more about this mobo)
ECS NF650iSLIT-A
ECS PN2-SLI2+

 

[castleking]

yes, you can use two card on a crossfire board without them being crossfired.

also, yes you can use 2 different cards of different types.

Awesome, thanks for your help!

 

[skyguy]

Actually, it sounds like there might be a wire crossed here......

You CANNOT have a multi-monitor setup for SLI. SLI only displays one monitor, end of story.

You CAN, however, have a multi-monitor setup for dual GPU, non-SLI configuration.

So, you can have 1 card power 2 monitors in non-SLI. You don't need a 2nd graphics card UNLESS you plan on having 3 monitors. If you're going with 3 monitors, then you can mix and match cards ONLY if you're running Vista, so that's fine. And yes, you can put 2 Nvidia cards in a Crossfire mobo (such as the ASUS P5B-Deluxe, for example) but again, not in SLI.


So, recap:
-2 monitors only needs one graphics card, pick any single PCI-e board you like
-2 monitors won't run in SLI
-3 monitors needs dual PCI-e board, whatever strikes your fancy
-3 monitors won't run in SLI unless you add a Matrox TripleHead2Go
-you can mix and match DX9 and DX10 cards if you want, but only in Vista
-you can put Nvida cards in ATI board and vice-versa, but cannot run SLI or Crossfire across platforms

So, which exactly are you trying to do??

 

[castleking]

Actually, it sounds like there might be a wire crossed here......

You CANNOT have a multi-monitor setup for SLI. SLI only displays one monitor, end of story.

You CAN, however, have a multi-monitor setup for dual GPU, non-SLI configuration.

So, you can have 1 card power 2 monitors in non-SLI. You don't need a 2nd graphics card UNLESS you plan on having 3 monitors. If you're going with 3 monitors, then you can mix and match cards ONLY if you're running Vista, so that's fine. And yes, you can put 2 Nvidia cards in a Crossfire mobo (such as the ASUS P5B-Deluxe, for example) but again, not in SLI.


So, recap:
-2 monitors only needs one graphics card, pick any single PCI-e board you like
-2 monitors won't run in SLI
-3 monitors needs dual PCI-e board, whatever strikes your fancy
-3 monitors won't run in SLI unless you add a Matrox TripleHead2Go
-you can mix and match DX9 and DX10 cards if you want, but only in Vista
-you can put Nvida cards in ATI board and vice-versa, but cannot run SLI or Crossfire across platforms

So, which exactly are you trying to do??

I was planning on taking the p965 mobo in the op, and put a x1600 or 7600 for the two monitors and a x1300 for the third monitor.

 

[skyguy]

Ok, that'll work. Don't expect blistering performance in games, but it'll certainly work for regular programs that benefit from 3 screens......Excel, Photoshop, AutoCAD, Radiant, Studio Viz, etc, etc.

 

[gramps]

Im glad you asked this question, its very similar to one I posted a few weeks ago (with no replies!!)
I wanted to do a similar thing, but with one workstation card (QuadroFX?) and one gaming card.
From all your answers it sounds like this would work... but can I pulg both cards into the same monitor? How would the computer know which card it should use - or would it just know because of the application? (QuadroFX needed to run Solidworks). Any other information/problems would be appreciated.

 

[skyguy]

Umm......how would you plug both cards into the same monitor? 8O

Do you mean both monitors into the same card?

 

[gramps]

Well I need it for both work and play - but cant do both at the same time!!
So a monitor with 2 DVI inputs is needed, so I can plug the 7900GS and QuadroFX into the same monitor? Or any other method you know of?
Really, I don't know how this would work, having a work/gaming card in the same machine - surely someone has done it before (and Im not going to build 2 separate rigs!!) - so any ideas would be welcome...

 

[hergieburbur]

Well I need it for both work and play - but cant do both at the same time!!
So a monitor with 2 DVI inputs is needed, so I can plug the 7900GS and QuadroFX into the same monitor? Or any other method you know of?
Really, I don't know how this would work, having a work/gaming card in the same machine - surely someone has done it before (and Im not going to build 2 separate rigs!!) - so any ideas would be welcome...

You could also get a monitor with a DVI and an analog input, and connect one card to each input. You can then use the input selector to switch between them.

I currently use one monitor for 3 PCs (2 via KVM switch) using this method.

 

[gramps]

Ahh, great, thanks, so I can use the one monitor (and not have to switch cables all the time).
But how about the setup? How will the PC know which videocard to use? When I run Solidworks, will it automatically output through the QuadrofX, and when I run a game it will automatically output through the 7900?
Or will I have to set one card to default (probably the 7900) and only enable the Quadro when I need it?
I have never even run and SLI setup before, let alone a setup with 2 different cards, let alone a setup with work & gaming cards...

 

[hergieburbur]

Never tried what you are asking about myself, but I think you can do this:

Connect the cards to the monitor as I said before.
In Display Properties -> Settings, select the "monitor" (The PC doesn't know they are the same) connected to the 7900 as the primary monitor.
UNCHECK the "Extend my Windows desktop to this monitor" checkbox.

When you want to run Solidworks, switch the primary display in Display properties to the QuadroFX and switch the input selector on the monitor.

When you want to switch back, just reverse the last step.

This should work for what you want to do, though like I said, I haven't tried it personally.

 

[gramps]

Ahha! :idea: Thanks, I think you've pretty much settled what I needed to know.
Now on to ordering and assembling!

Thanks again...

 

[hergieburbur]

No problem. Just post back if you need any more.

 

[NaDa]

How will the PC know which videocard to use?

Usually there is an option within a program or a game that lets you chose which video card to use.
If this doesnt work then you will probably have to manualy switch the card you want to use to be you primary adapter. (Control panel->Display)