CrossFire, two cards, confused!!

[Shad]

I'm a bit confused by the whole ATI CrossFire dealio. I thought that to have two ATI cards in a system, they needed to be connected (crossfired) somehow, presumably with a little cable thingy. I've got a 3850 at the moment but I've just ordered a 4850 (partially by mistake).

Question is, will these two cards crossfire? Does it matter - will they work happily without being crossfired? I need to run 4 screens hence the two cards, not bothered about gaming performance really (at worse I guess the games will come out of the 4850 since it's faster?).

Help appreciated!

[shadowmaster]

I'm a bit confused by the whole ATI CrossFire dealio. I thought that to have two ATI cards in a system, they needed to be connected (crossfired) somehow, presumably with a little cable thingy. I've got a 3850 at the moment but I've just ordered a 4850 (partially by mistake).

Question is, will these two cards crossfire? Does it matter - will they work happily without being crossfired? I need to run 4 screens hence the two cards, not bothered about gaming performance really (at worse I guess the games will come out of the 4850 since it's faster?).

Help appreciated!

You can crossfire a 3850 with any 38** card, so it wont work with a 4850.

In regard, to whether they will work together outside crossfire, I don't think so.

[Shad]

So I can't have the two cards in the machine (not crossfired) to run 4 monitors??!

[Splash]

I see no reason why you couldn't do that, but as Shadowmaster says they won't work in Crossfire. They both use the same drivers, so you should be fine.

[TAKTAK]

You should be able to run both out of crossfire, you can't crossfire them though...

It might be an arse to setup , but it should work..

[Shad]

Ok, phew, thanks!

I'm not bothered about game performance though I'll probably replace the 3850 with a 4850 at some point.

Presumably if monitor 1 is running on the 4850, and the game is running on monitor 1, the game will use the 4850 rather than get confused and use the 3850? Would is be possible to run a game spanned across two screens that use each card?

[shadowmaster]

http://game.amd.com/us-en/content/im...ombo_chart.jpg

Just to confirm, crossfire wont work. But as the above two say it may work normally.

[TAKTAK]

Ok, phew, thanks!

I'm not bothered about game performance though I'll probably replace the 3850 with a 4850 at some point.

Presumably if monitor 1 is running on the 4850, and the game is running on monitor 1, the game will use the 4850 rather than get confused and use the 3850? Would is be possible to run a game spanned across two screens that use each card?

Now that one, i have no idea about...

But would be interesting to find out...

I'd imagine it would be quite hard to do...

[Shad]

I suspect that's what crossfire is designed to achieve (spanning multiple monitors across cards).

As long as the setup will support 4 monitors that's the main thing. And ideally not crash if I try and load a game!

Thanks very much everyone

[Funkstar]

I haven't tried it, but I would suspect that a game (DirectX really) will favour monitor 1 when you load it, just like the first time it's loaded, any app window will open on the primary monitor.

And yes, the Windows drive model is designed to use multiple card for multiple screens as long as they are based on the same driver pack. You couldn't use one ATI and one nVidea, or even a current ATI and a legacy PCI one for example as they will be different driver packs.

The only reason for the "should" and "maybe" is down to bugs or design faults in that driver pack causing issues, as I said, this is how the Windows drive model is supposed to work.

[Bondi]

Just say you have monitor A plugged into your 4850, if monitor A is set as the default monitor (Main 1st Monitor) I should think it would use Monitor A on the 4850 because its set as default, but if you set monitor D as the default monitor on the 3850 then it should use the 3850.

Correct me if I am wrong.


- Bondi

[TAKTAK]

You couldn't use one ATI and one nVidea

You can

[Splash]

You can

...caveat being that it's a pain in the arse to setup and requires very specific hardware.

[TAKTAK]

...caveat being that it's a pain in the arse to setup and requires very specific hardware.

This ^^, some boards just through a paddy fit (i think shaithis had problems with DFi over it), and it adds a whole new set of problems to the mix, but it can be done

[Funkstar]

You can

Thats news to me. Sounds like it's a recipe for disaster and an unstable system to me though.

[this_is_gav]

You can't in Vista, but can in XP and apparently 7 too, though with XP it used to be a huge pain to do it. Don't know how easy it is now.