Could this be why my crossfire setup has problems?

[enaberif]

For whatever reason the one card runs slow than the other..

What happens when you run the cards in CF? Do they run at the same speeds? And which does it default down to?

[akulacan]

Typically the faster card will downclock to match the slower card but I'm not sure about this. Is there a way to check it in real time?

When CF is enabled, both cards keep their speeds. Ives tried overclocking one card to match the faster one and downclocking the faster card to match the slower one. None of these measures made a difference. I did notice that despite the fact that they are 5850s, the boards are different sizes.

Man what a headache!!! Anyone wanna trade my faster powercolor 5850 for an asus EAH 5850?

[JD]

Do you know if both cards are reference PCB? If so, you could flash the same BIOS to both cards. Might help.

I have a Sapphire (reference) HD5870 and recently paired it up with a Vapor-X HD5870 (the newer non-reference PCB) and it seems to work fine in BF:BC2. I now get a solid 60FPS (v-sync'd) on maximum settings including AA/AF which I couldn't do with a single card.

Are you using the latest Catalyst drivers? Did you install the Application Profiles?

[akulacan]

Questions: what does reference PCB mean? How would I check that?

Using cat 11.2 and I have installed the application profiles but haven't used them yet.

[Kommie986]

Originally Posted by akulacan

Questions: what does reference PCB mean? How would I check that?

Using cat 11.2 and I have installed the application profiles but haven't used them yet.

Whether your cards are AMD reference design or manufacture (Asus and Powercolor in your case) design.

[headsh0t]

That's the first thing I was thinking when I read OP is that one card is reference and the other is non-reference. How to tell if the card is reference design or not? HOW TO: Tell an ATI 5xxx Reference card from non-reference - Overclock.net - Overclocking.net

[Kommie986]

This: http://www.coolingconfigurator.com/i...erence-PCB.jpg might also be helpful.

[Dr_BenD_over]

The first number is a date code, the second is probably a lot code. Issues with CF are normal, as much as people will flog how great it is, it doesn't always work.

[akulacan]

Originally Posted by Dr_BenD_over

The first number is a date code, the second is probably a lot code. Issues with CF are normal, as much as people will flog how great it is, it doesn't always work.

I agree, CF and SLI are wayy too overrated and just a false hype designed to drain the wallet. I think next time I'll just go single SOLID card instead of dealing with the headaches.

[rjbarker]

^^^^ I've never had any issues at all running Multi SLi configs.....no "Hype" at all as far as I'm concerned, I've always seen huge gain going to x2 and good gains going to x3 (Tri SLi)....every now n the we hav to wait for a new Driver release that will enable SLi function in some games...

Now you say you're getting poor FPS running a particular game...what Res and are you expecting excellent FPS with those 2 Cards? Correct me if I'm wrong but are the 5850's extremely "potent" Cards? Have you tried running / comparing some Benchmark runs with 1 Card vs 2? Could just be those 2 Cards / Driver doesn't play nice with tht particular game.....

What do you mean by poor FPS?