Crossfire Questions & 5970 vs 5850 CF

[Patrick Wolf]

I only have SLI experience w/ a single 9800 GX2 and am wondering how it differs from CF.

1. In SLI you can set it so only one GPU is enabled, can you do the same in CF with either a single Multi-GPU card (5970) or 2 seperate cards (5850 CF)?

2. In SLI you can change the Multi-GPU mode for games that don't support multi-GPU setups to Force Alternate Frame Rendering 1 or 2. Can you do the same w/ CF? Same options, or different?

3. This question kinda depends on 1 and 2. Not all games support CF (I think?). If this is the case; would running a 5850 CF in single GPU-Mode give better performance than a 5970 in single GPU-Mode?

Thanks in advance.

 

[Sylvanas]

I only have SLI experience w/ a single 9800 GX2 and am wondering how it differs from CF.

1. In SLI you can set it so only one GPU is enabled, can you do the same in CF with either a single Multi-GPU card (5970) or 2 seperate cards (5850 CF)?

2. In SLI you can change the Multi-GPU mode for games that don't support multi-GPU setups to Force Alternate Frame Rendering 1 or 2. Can you do the same w/ CF? Same options, or different?

3. This question kinda depends on 1 and 2. Not all games support CF (I think?). If this is the case; would running a 5850 CF in single GPU-Mode give better performance than a 5970 in single GPU-Mode?

Thanks in advance.

1. CF is enabled by default and there is no visible 'enable CF' in the driver for a 3870x2/4870x2/5970 card. However, since the introduction of 'Catalyst AI' in the driver many years ago, one could force disable of CF by setting AI to 'disabled'. This is silly however as you miss out on the performance benefits of Cat AI and I'm not sure if it still works like that these days.

For two single cards you can enable and disable CF as you please.

2. Not really. There is no nhancer software for ATI except ATI tray Tools and I'm not sure if that allows the switching of different CF modes (AFR, Supertiling, scissor mode). However AFR is enabled by default with Catalyst AI on Standard or Advanced.

3. Now that ATI have made their driver more modular they are able to push out CF profile updates very quickly, so no doubt newer games should all be supported come launch day- if they're not it won't be a long wait. It is getting pretty rare that an established game doesn't have a CF profile, and if it doesn't it likely runs maxed on single core.

Answer to your question is if there is no profile for your game, the game will run on GPU1 by default and not use the other.

 

[Patrick Wolf]

Excellent, Sylvanas. Thank you!

Crossfire sounds nice.

 

[lavaheadache]

Crossfire is nice. I have been a very satisfied user. Seems a little bit more polished than all of my other Sli setups

 

[NoQuarter]

3. This question kinda depends on 1 and 2. Not all games support CF (I think?). If this is the case; would running a 5850 CF in single GPU-Mode give better performance than a 5970 in single GPU-Mode?

I'd imagine the 5970 in single GPU-mode would be faster than a single 5850 since it's a dual 5870 clocked at 5850 speeds.

 

[Hauk]

Crossfire has come a long way and will likely continue to improve. AT's article http://www.anandtech.com/show/2940 makes clear that ATI is focusing on driver improvements. They seem very focused; with these driver improvements, it seems clear they intend on keeping pace with nVidia's well perceived multi-gpu support.

With SLI, I really like the scaling bar indicator that can be displayed while gaming. I test each game with it to be sure SLI is scaling okay. ATI *needs* an indicator of some type..

 

[Madcatatlas]

I wonder what the requirements for mechwarrior 5 will be in terms of GPU/CPU power. Maybe a CF 5770 or 5850 is futureproof enough? i reckon it will be out in a year or two on cross platforms.

also: like your avatar Hauk! go weapons hot!

 

[Harrod]

wrong post

 

[Rhoxed]

Crossfire has come a long way and will likely continue to improve. AT's article http://www.anandtech.com/show/2940 makes clear that ATI is focusing on driver improvements. They seem very focused; with these driver improvements, it seems clear they intend on keeping pace with nVidia's well perceived multi-gpu support.

With SLI, I really like the scaling bar indicator that can be displayed while gaming. I test each game with it to be sure SLI is scaling okay. ATI *needs* an indicator of some type..

ATI *has* an indicator!
right click the CCC bar on your start bar, go to top video card, go to crossfire X settings, and click on "show crossfireX icon where applicable" then an ATI icon will show up in any game with xfire.

 

[lavaheadache]

ATI *has* an indicator!
right click the CCC bar on your start bar, go to top video card, go to crossfire X settings, and click on "show crossfireX icon where applicable" then an ATI icon will show up in any game with xfire.

found it thanks