To Crossfire or not?

[Thunderboy]

Hi all, thanks in advance for any help/insight you can provide.

Rebuilding one of my PC's and am faced with the choice of using one or both of two available GPUs. The GPUs in question are:

Sapphire HD 6950 1Gb (non-ref)
Gigabyte HD 6970 2Gb

As I understand it (and my understanding is admittedly limited), were I to put the two in Crossfire, the 6970 would run at the same speed as the 6950 and the whole system would only provide 1Gb VRAM.

The question:

Would I be better off using the two in Crossfire, or just the 6970 by itself?

I run three monitors in Eyefinity and do some flight-simming, so best performance is obviously what I am looking for.

Thank you!

 

[deadjon]

Im not sure about the 1gb version.

The reference 2gb 6950 will Crossfire with the 6970 fine

Being a non reference card I Dont think it will Xfire with the 6970 at all - as the Xfire on relies on it being a pretty much IDENTICAL card, with a different BIOS

 

[Thunderboy]

Ah, interesting. Thanks for the information.

Most likely, I'll just end up buying a second 6970 in a few months, anyway.

 

[chesteracorgi]

Ah, interesting. Thanks for the information.

Most likely, I'll just end up buying a second 6970 in a few months, anyway.

As long as you take anti-statci precautions and do not overvolt the cards you might as well try to Xfire them anyway. If you seat both in your mobo and boot up the first video card should be used a default and you should see options (or not) regarding Xfire. Anyway, it won't hurt to try.

 

[PGRacer]

Being a non reference card I Dont think it will Xfire with the 6970 at all - as the Xfire on relies on it being a pretty much IDENTICAL card, with a different BIOS

Not at all I had a sapphire 4890 Vapor-X OC 2GB crossfired with a Club 4890 1GB Suprclocked Edition. It will only use 1GB on both cards though. But they were completely compatible.

I would stick with the single 2GB card, sell the 1GB card and put a tiny bit with it so you can get a 2GB card to go with the first one.

 

[Thunderboy]

Wow - didn't expect so many responses so quickly. What a great forum!

So, ultimately, the benefit of the single 6970's extra memory outweighs any benefit I would see from putting the two cards in Crossfire (providing it is even possible)? I ask more for personal understanding, as I'm pretty sure I'll just go ahead with the single 6970 for now.

Thanks again!

 

[ringzero]

Wow - didn't expect so many responses so quickly. What a great forum!

So, ultimately, the benefit of the single 6970's extra memory outweighs any benefit I would see from putting the two cards in Croosfire (providing it is even possible)? I ask more for personal understanding, as I'm pretty sure I'll just go ahead with the single 6970 for now.

Thanks again!

You would get better performance NOW if you crossfired them, but my advice would be to wait until you can crossfire two 6970 2GBs. Unless you've already opened your 6950. If so, might as well use it until you can afford the second 6970 and sell it used then.

 

[Thunderboy]

Ah - they are both open and used already (I have several PCs worth of parts I am pulling from), so I'll see if the two cards work together, then. At least until I can get another 6970. It's going top have to wait until after the holidays, though.

Best to you all!

 

[djridonkulus]

Since you already own the two cards, just crossfire them. I'm surprised nobody provided you with the Crossfire Compatibility Chart:

http://sites.amd.com/PublishingImages/Public/Graphic_Illustrations/WebBannerJPEG/AMD_CrossfireX_Chart_1618W.jpg

Source:
http://forums.amd.com/game/messageview.cfm?catid=262&threadid=142339

Your two cards ARE compatible though not recommended.

As someone who crossfires, I regret it. The microstuttering issues are annoying. The catalyst application profiles never get it right and it always seems as if they fix one problem in one release, but recreate a previous problem. They just can't seem to get it ALL right.

As I said, since you already own them both, don't waste them, crossfire them.

 

[Thunderboy]

Ahhh - thanks, ridonk.

I'm usually pretty good at finding whatever info I need on the webz, but it's been a long night. The links are much appreciated.

Thanks for all the help, everyone, I think this topic is done!