Does UDK work with Crossfire or SLI?

[mux85]

Hi everyone, I'm thinking about upgrading my pc and I was considering the possibility of getting a Crossfire or SLI system (probably using two Radeon 6850 or 6870 or geforce 560 ti). Would it work well with UDK? Someone has some experience to share about this?
Many thanks.

[Linkinworm]

it should work from other posts i read on here usualy it splits the load so each card uses only 50% i think loweing heat on each card

[mux85]

So there will be no performance improvement using two graphics card in UDK?
Anyway the important thing is the compatibility of UDK with Crossfire or SLI so that there will be no crash (no more than usual :P) or features not working because of multiple GPU.

[TheAgent]

Crossfire or SLI should work just fine. You will get a large performance gain, with double the cards. Sometimes Crossfire has issues where it doesn't work. SLI so far i never had problems.

[mux85]

Good to hear that. What graphic cards do you have?

[Sheff]

As i figured out SLI is not supported by the engine anymore. I tested 2x 590 cards in SLI and QUAD SLI and it didn't give me any performance... It gave me only 2-4 additional frames in one of the SLI modes, and i think it's like nothing...

http://forums.epicgames.com/threads/...K-supports-SLI

[WedgeBob]

Well, I only have single GPUs on both my systems, and performance hasn't bottlenecked. My laptop has a GT 420M and my desktop has an HD 5850, so two different brands of GPUs, so that way some of my work is done through nVidia and some is done through AMD... So to me, I feel that either way will work equally with UDK. Can't really judge on multi-GPUs, but I assume you will be fine.

[ironbelly]

From what I understand UE3/UDK is a more CPU focused engine than say CryENGINE so you are no doubt going to see your largest performance gains from an upgraded CPU than you would doubling your GPU's. Not saying it ignores the GPU but it seems that a faster CPU, pound for pound, makes more of a difference than a faster GPU after you reach a certain level.

[Sheff]

How about 2x CPU system, will it give more frames then 1x PCU configuration?

[xThe OmegaX]

I dont wanna make a new topic on the same thing, so Ill bump this old one. So how do I get crossfire to work in UDK. I have 2 5830's but when I open UDK one stays at 0% the whole time. Also is it normal for one card to be at 100% all the time? UDK doesnt seem laggy at all. I know 5830 isnt the best, but its not that bad of a card

[mktwo]

The editor does not use the extra card, the game you make with it should!