BleepingComputer.com: Some questions about crossfiring

should work ok, I cannot garentee there wont be any kind of issues between the mix matched memory. In theory, there shouldnt be, but theres no garentee when it comes to multiple cards. It will run find, the most you might have is some texture issues I would imagine.

Texture issues now?!?

I dont know-some things are weird when it comes to a dual video card setup, they have their quirks. Let me give you an example, with my system, using dual ATI 4890 video cards, same specs, the only differnce is brand (ones ASUS the others Saphire) both cards are identical, so in theory they should work well together right? well with the latest ATI drivers, they will not display water in battlefield bad company 2. Now, if I use an older version of the driver, it displays water just fine. So even with identical cards, I had to play with the drivers to get it to work properly.

With the 4890 and 4850, it would mess up the textures of objects at long range-for example, brown boxes would appear black when looked at from range with a sniper scope. I never could get around that, Im pretty sure it was the memory mismatch (4890 had 1 gig gddr5 4850 had 512mb of gddr3) So the reality is, you wont know for certain until you get it hooked up. Drivers with multiple GPUs turn into a nightmere as often as not. That being said if you stick with it, the reward is usually worth the added effort, and usually the side effects are little more then slight annoyances.

I'm trying to call AMD right now.

Disregard

This post has been edited by killerx525: 13 July 2011 - 11:25 PM

like I said-they should work together just fine. You may/may not have some texture issues-but its next to impossible to tell until you get them hooked up, and even then it may be as simple as trying different versions of the drivers, its just the nature of the beast.

I called up AMD and there was no tech available so they called Singpore AMD and they said the GDDR3 and GDDR5 should work fine together. I still have more questions for them how many crossfire bridge is needed and driver/texture issues that might rise.

Like I said one should be fine-even if its not theyre cheap addjing a second is no big deal. As far as texture issues, they wont know-they cant test every configuration possible thats gonna be something that you will have to find out once u get the cards hookup. If u do have any issues I suspect they will minimal, if I had to put money on it, but if not they will be fixable

I got some answers, there should be no texture or driver issue. The different memory type should be fine and the faster card will go slower so it can match the slower card. I only need 1 crossfire bridge. I gave the link to my card and the second card which the person checked through their database which came up with compatible or something.

This post has been edited by killerx525: 14 July 2011 - 11:32 AM

Lol then they don't know what they're talking about-like previously mentioned, ati cards dont downclock, they dont have to their built that way. As far as the texture issues, the textbook answer is they wont-but what happens in the textbook doesn't always happen in life

What they have is a tech who tries various configs out, and write down the results-the person you talked to looked at their cheat sheet which says that it will work flawlessly. What they dont-and can't know is how well the drivers will work with your other components-which is where most of your texture issues will come from-driver conflicts

Oh, so it's really up to me and see which driver will work flawlessly, right?

pretty much-like I said, those cards will work fine-they just may not be plug and play you may have to tweak them some. Usually not a big issue.

Also keep in mind, that crossfiring two cards with an older/weaker CPU has its drawbacks-especially in CPU intensive applications. Now, that CPU has to send instruction sets to two cards instead of just one. The fact they are linked means it wont be a huge draw, not as much as having two independent cards running-but it will nonetheless. With high end CPUs, this is barely, if ever noticed-with older or weaker CPUs, especially with modern CPU intensive programs and games such as BFBC2, it may have adverse affects. I dont know how exactly it will handle, it may do just fine, but just to give you a heads up.

No i plan to use this with a i5-2500. So i doubt there would be any bottleneck with it.