5850 + 5870 crossfire

[x13killer]

I've gotten my eyefinity to work with 2x 23" screens and a 22" in the center
Now that that problem has been worked out, i have another.
The OC'd 5850 that i'm running is understandably struggling on some of the games to run it at this insane resolution

It's been about 6 months since i got my 5850 and now the 5870's are around the price that the 5850 was
I'm thinking about getting a 5870 to cf with my 5850 to get some extra power to play the newer games.

Has anybody here done this? I've read articles about people doing this and they say that the 58xx series is capable of using both the cards at their maximum capacity despite being different.

Any thoughts and advice would be greatly appreciated.

 

[nforce4max]

I am not sure about eyefinity being a factor but you can crossfire a 5850 with a 5870 just fine.

 

[jryan388]

... is generally slower than double 5850 crossfire ...
But yes it works, and is better than either single card.

 

[nforce4max]

... is generally slower than double 5850 crossfire ...
But yes it works, and is better than either single card.

That seams to contradict the pattern established during the 3k and 4k generations. It wasn't as fast as saying being two 5870 but still slightly faster than two 5850 if there isn't any clock synch involved.

 

[x13killer]

I was wondering if there would be any abnormalities like not performing as well as 2x 5850s
Anybody know of any benchmarks?

 

[nforce4max]

You can search through for a article/review posted last year here on THG with the very same cards with even the 5830 is included. It is very relevant to your question.

 

[purple stain]

Wouldn't the 5870 just be underclocked to the 5850?Why would he buy the 5870 for more than a 5850 if it's just going to deliver the same performance.Even if you bought the 2G versions of the 5870,which could be very useful in an eyefinity setup, you still couldn't use the extra 1G anyway.Just doesn't make sense to me.

 

[nforce4max]

Wouldn't the 5870 just be underclocked to the 5850?Why would he buy the 5870 for more than a 5850 if it's just going to deliver the same performance.Even if you bought the 2G versions of the 5870,which could be very useful in an eyefinity setup, you still couldn't use the extra 1G anyway.Just doesn't make sense to me.

Even with the minor downclock there is still the extra shaders on the 5870 that will still be running. at least sli allows for asymmetric clocking and shader counts vs crossfire.

 

[x13killer]

Last i checked, the clocks would stay the same. I heard that they changed that going over from the 4xxx series to the 5xxx series and that both cards would preform to their peak.

 

[iam2thecrowe]

http://www.legitreviews.com/article/1107/5/
looks like its not worth it, may aswell save the cash and get another 5850. Or even better sell the 5850 and get the 6850xfire, then new 6xxx series scales better in dual card config.