Direct X 11 performance in Alienware m17x R2 crossfire Amd Hd 5870m?

I would like to know what is the performance level of R2 crossfire setup when playing games with DX 11 turned on.

Thank You in advance

 

You've asked a very open-ended question, and I doubt you're going to get a single 'good' answer to it. But here's my $0.02.

Let's assume that you've got DX11-capable cards in your system, that you're running a single set of drivers, and the only thing you're doing is switching between DX10 and DX11 in the game. In that case, the change in performance is directly related to what DX11 is used for and how well those DX11 features have been coded.

Battlefield: Bad Company 2 doesn't do a lot with DX11. All it does is to add in a few rendering effects, so it doesn't add a lot of complexity to the scene. In this case, turning on DX11 doesn't seem to affect game performance to any noticeable degree.

Metro 2033, on the other hand, enables quite a few effects with DX11. Tessellation is turn on, which makes surface textures and smoke/fog effects more realistic. You can also enable Advanced DOF, which blurs objects depending on their focal length and where you're looking (like with photos where the subject is in focus but the background is blurry). I don't know if it's the graphics drivers or the game code, but these DX11 options can noticeable drop the game's performance.

So that's same hardware/same drivers. But you also have to be aware that different drivers also effect DX11 performance. For example, the latest ATI/AMD 11.2 drivers work better with Metro 2033 than the official Dell 8.763 drivers. The reason for this is that AMD have optimised their drivers over time. Sometimes a game will bring out a flaw in AMD's code, and they'll fix it. Other times AMD will discover that a game is doing something inefficiently, and will add fixes to their code that work around the game issue. Either way, newer drivers often make older games work better.

So there you go. Not a simple answer, but hopefully it at least explains why you'll never get a simple answer to your question.

 

tessellation is one of the singe most useless things our gpu's can do. one because they do it poorly, and two because it drops performance by a large degree.

so large performance drops for little to no visual upgrades.

 

what nzgeek said and one more thing.

Usually with 5870's if the game is "nvidia the way it's meant to be played" we don't get that much of performance.

Metro 2033 is the case (and the developers are kind of nvidia Fanboys too)

 

It depends on the level of tessellation. If the game only does a little bit of tessellation, you don't get much slow-down, but you don't see much difference in graphics either. You're more likely to see the effects of higher tessellation levels, but of course you'll get more slow-down.

The newer ATI drivers (from 11.2 on, maybe 11.1) allow you to control the level of tessellation in games. The default is driver-controlled, which allows the drivers/CAPs to turn down the level if it decreases performance too much.