AMD 6850 CrossFireX Not Working

I have noticed lower FPS while running AMD CrossFireX after installing my second graphics card. I am running World of Warcraft averaging 40 FPS with CrossFireX and 50 without. While tabbing between the desktop and the game my screen will sometimes change the color of the window to its opposite for a second and then go to either the desktop or the game. WoW will turn blue, my Windows 7 blue desktop will turn orange. After reading some post I tried reinstalling the drivers and with the latest driver I began crashing on top of my problem of CrossFireX not working. I enabled the ingame icon to be sure that it was actually on which is was. I have some concern about my new motherboard that I just purchased. I did not realize that the PCI-E ports are x16 and x4. I have read numerous reviews about this subject being bad or being good. I really do not want to replace the motherboard but if I have to I will. I hope that one of you experts can help me out with my problem.

Motherboard: ASUS M4A87TD EVO
RAM: Crucial Ballistix sport 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1333 BL2KIT51264BA1339
Video Card: XFX HD-685X-ZNFC 6850 AND SAPPHIRE 100315L 6850
PSU: CORSAIR Professional Series HX750
Monitor: HP S2031 (DVI CONNECTION)
Hard drives: THREE -- 2 INTEL SSD -- 1 WD HD
Optical Drives: ONE
Additional PCI cards: NONE
Number of fans present: THREE

Operating System: WINDOWS 7 X64
Video Card Drivers in Use: LASTEST
Motherboard Drivers Used: NOT SURE
Apps/Games causing issues: WORLD OF WARCRAFT

Thank you so much for your time!

Happy Thanksgiving!
Joel Howard

Update: After switching the graphics card slot I noticed the performance in the x4 slot was 1 FPS higher then the performance in the x16 slot. I was averaging 45 FPS in the x4, tested both card ports, and 44 FPS in the x16 slot on single mode on both cards. I tried CrossFireX on both slots averaging 44 FPS and was still getting the color problem while changing between windows.

I have been trying to switch around the cards and re install different drivers. I discovered that if I plug the DVI cable into the bottom or the top card during boot and enable CrossFireX the opposing card no longer works if I change the DVI cable to that card. I do not know if that is normal or not.
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More about 6850 crossfirex working
  1. First the slowdown issue; I too had a x16 x4 board that I tried to xfire w/2 HD 6850s. Same situation. Some games showed a tiny increase in framerate. Some games showed a decrease in framerate. I finally decided that the x4 slot didn't have the bandwidth and was slowing the other card down. So I moved them to my main machine that has x16 x16. (But all you really need is x8 x8) Now they fly!

    Now the graphics corruption issue; Always uninstall the existing driver from control panel before installing the new one. Even better, then run Driver Sweeper from safe mode to remove any remnants. Reboot and install the new driver.

    Another possiblility, if your machine has been in use for a long time, is resource wasting garbage that has collected, and registry errors. Run CCleaner and do the Clean and Registry both. Reboot. Defrag.
  2. That is what I have figured. I really appreciate you coming on and giving me a response to this problem today. I ordered a new motherboard Asus Sabertooth from Newegg last night on sale for Black Friday. I will RMA my board and use this one. I read up and found that this one is top quality for Crossfire and SLI with x16 x16. I tried removing all of the drivers and re installing them multiple times. Could that just be an issue with there being two different cards? I used the disk from my XFX box and it said that I need to download optimized drivers from the website. I wasn't able to install the ones directly from the disc. I also noticed if both cards are linked when I do the install it says warnings occurred during the installation and it will not let me read the log to find out what they were.


    After removing the bridge while I wait for the new motherboard my FPS jumped up 10 FPS on both single cards.. Idk what that means but it is better.
  3. If both HD 6850 cards have the same memory, speed, etc, there should be no problem according to the AMD site. I originally had a Sapphire and a HIS working together until I swapped the HIS for another Sapphire and put the HIS in a build I sold.

    When it comes to drivers for mixed cards, I would use the driver pkg from the AMD site. The boxed drivers are outdated, and I'm always concerned that they may contain proprietary code for their specific card. Since you too are using mixed brands, that may be an issue.

    And don't forget to uninstall the old driver/CCC pkg before installing the new one.
  4. Okay so I got my new motherboard which seems great. My OPS is higher by about 10 OPS depending on where I am in WoW. I have not switched cards and am still seeing strange colors while tabbing between Windows. Any idea of what I should try? Older drivers possibly? Switching RAM spots? What programs can I run to test my build that are designed for crossfire?

  5. Does the color corruption only occur when alt-tabbing out of WoW to the desktop? If so, I would have to assume it's an issue with the games software code. It's not releasing the graphics fully back to Windows. Alt-tabbing out of any game to the desktop has always been an iffy situation. Most games don't even allow that anymore.

    Test your framerate and card temps with Furmark, if you're looking for comparative benchmarks. If you're looking for games to test the xfire speed, Metro 2033, Crysis, FEAR, and Far Cry 2 have time demos/benchmark pgms. S.T.A.L.K.E.R.: Call of Pripyat Benchmark is a stand-alone benchmark you can download: , and Unigine 'Heaven' DX11 Benchmark is a good DX11 benchmark: And of course there's 3D Mark and Passmark's Performance Test.
  6. Great! I figured that it could just be the game. It only happens when tabbing between Windows. I am still nervous that it could be just from my motherboard overclocking the CPU higher. (WoW is a heavy CPU game) I tested SC2 which I also believe is a CPU based game and I was getting 20 more FPS on SC2. I will download the test tonight and give it a try. I wish this wasn't so difficult to make it work! :(

    I will report either tonight or tomorrow with my findings!

  7. If you want to compare your framerates with my system, I think I can find my benchmarks somewhere from when I ran the time demos that I listed. We have fairly similar systems. Both with HD 6850s in xfire @ x16 x16... or are you still using the x16 x4 board now?
  8. I got the ASUS Sabertooth x16 x16 board. Which one are you going to be testing on?
  9. HAF 912, Gigatbyte 990FXA-UD3, Phenom II X4 980, Zalman CS5 HSF, 8G Kingston 1333MHZ, 2 x HD 6850, WD Caviar Black 750GB, XFX 850W PSU.
    Apparently you're not signed it, so you don't see my rig in the signature below my name.
    I already ran the tests. I saved the results to my network HDD.
  10. I ran FurMark latest version and was getting a steady 60FPS the whole time. My rating was 3.5k and I had all of my graphics card settings maxed out. AA Filter x16 blah blah texture to the max.. all that jazz. I was comparing it to some others but I noticed my screen resolution was 1600 x 900 not the default size. Also, I moved WoW to my SSD and my loading times increased and I generally have 60FPS all the time unless there is a lot going on or I am in a major city. Sorry it took so long to reply!

  11. AA filter @ x16? Do you mean AF? Mine crawls at anything over 4x AnitAliasing. AF @ 16x, however, makes little difference to mine. And I'm running Furmark 1.9.1

    Btw, to the best of my knowledge windowed mode turns off Crossfire. Only one card will be active. At least on mine. There may be ways around that, but I haven't bothered to find it because I game at full screen always.
  12. What was your score with FurMark sir?
  13. I ran Furmark V 1.9.1 full screen at:

    - your monitor's resolution of 1600x900 with NO anti-aliasing
    - your monitor's resolution of 1600x900 with 4X MSAA (anti-aliasing)
    - my monitor's native resolution of 1920x1080 with NO anti-aliasing

    The results I got are here:

    One odd thing I noticed when the results were presented; it always reports an average FPS lower than the minimum FPS. How the heck can that be possible?
  14. Hey dude sorry to disappoint you, but WoW doesn't support neither CrossfireX, nor SLI. That should explain why you're actually getting worse performance. What about other games? Are they working faster with CrossFireX enabled?
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