1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

    Dismiss Notice

DX11 & Crossfire not compatible

Discussion in 'Graphics Cards' started by Jay_t, 21 Apr 2010.

  1. Jay_t

    Hitman

    Joined: 19 May 2005

    Posts: 714

    Location: The Lake District

    Hi,

    Having tried several 5850 crossfire combinations on different PCs and with 3 different matched pairs of 5850s, I'm concerned about tesselation in DX 11.

    All cards can run tesselation on there own, but in crossfire mode it crashes the PC. If tesselation is enabled in Metro 2033, Dirt 2 (Crowd setting on ultra) or the Unigene engine, whilst crossfire is enabled, the PC Crashes. I've tried 3 sets of ATI drivers without success.

    Whats going on here? Tesselation is the main feature in DX11. I bought a pair of 5850s so I could enable this feature, not have to turn it off.:(
     
  2. unp|dissy

    Wise Guy

    Joined: 22 Feb 2010

    Posts: 2,187

    Location: Chester

    It's fine for me..

    What drivers are u you using? Have you installed application profiles etc..

    dx11 is installed correctly isnt it? :)
     
  3. Baboonanza

    Wise Guy

    Joined: 10 Nov 2009

    Posts: 1,099

    Location: London

    Yeha, if this was a widespread problem we would have seen a lot of shouting on here already.
     
  4. Geckovich

    Wise Guy

    Joined: 27 Nov 2008

    Posts: 2,266

    Location: Cambridge

    Fine for me too.
     
  5. {SAS}TB

    Soldato

    Joined: 20 May 2007

    Posts: 6,182

    Location: Location: Location:

    Fine here - hope you get it sorted :S
     
  6. UKDTweak

    Soldato

    Joined: 2 Dec 2002

    Posts: 6,592

    Location: N.Ireland

    I think something else is causing the problem as there are no reports of this fault in all the time the DX11 ATI cards have been available, and there are plenty of members on this furum runnning Crossfire...

    Have you run any stability tests, stress tests on your system and VGA cards?

    Have you tested without the 5850's overclocked?
     
  7. Jay_t

    Hitman

    Joined: 19 May 2005

    Posts: 714

    Location: The Lake District

    Thanks for the replies so far guys - I knew this would probably be the best forum to get help with this.

    • I have the latest bios on the motherboard.
    • I have tried with the cards and i7 chip running at stock settings.
    • The system is prime 95 stable for 48 hours and can run intel burn test for hours on end.
    • The graphics cards have been tested at stock and overclocked on furmark.
    • I have tested several pairs of cards, without seeing any difference.
    • Currently I have the latest app profiles installed together with Cat 10.3's.
    • I have reinstalled Windows 7 Ultimate x64 twice to rule that out.
    • Other 5850 users seem to have the same problem. http://forums.guru3d.com/showthread.php?t=318451

    Keep the ideas coming guys - thanks.:)
     
  8. BigBruiserAl

    Mobster

    Joined: 11 Sep 2008

    Posts: 3,322

    Location: Co. Durham

    +1
     
  9. UKDTweak

    Soldato

    Joined: 2 Dec 2002

    Posts: 6,592

    Location: N.Ireland

    Tested with Furmark?

    I did a little testing with Furmark lastnight...

    With my card running at 850/1200, all tests were spot on and games run sweet... Furmark score of 4017, with my card at 900/1250, again Furmark ran fine in both Stability Burn tests and in benchmark mode scoring 50xx, but when I try to load a game or even 3D Mark Vantage... the driver stops responding and the app crashes.... so Furmark is Not the best test to show stability in games!
    Perhaps your overclocked 5850's are not a stable as you think?

    If you run both cards at Stock in crossfire... do your games still crash?
     
  10. jorzeh

    Wise Guy

    Joined: 20 Jun 2009

    Posts: 1,432

    Location: Stockport

    Sounds like a Weak link one one of the cards crossfire controllers you or the bridge is damaged ?

    Try xfire 2 of the cards alternate one might needs to be RMAed and check the firmware of the cards is the same and upto date.

    i mean like Card 1 - 2 then try 1 - 3 together then 2 - 3 one might be causing the others to crash. (little label wit number)

    Tell us how you go on.
     
  11. ebilcake

    Wise Guy

    Joined: 18 Oct 2007

    Posts: 1,367

    Working fine here, no problems running Heaven 2.0 benchmark with DX11 with HD5870 CF.
     
  12. straxusii

    Mobster

    Joined: 18 May 2003

    Posts: 4,886

    If you can try a different PSU, doesnt sound like it's the culprit given furmark is stable but I guess cf tesselation might push the cards more or in different ways?
     
  13. Jay_t

    Hitman

    Joined: 19 May 2005

    Posts: 714

    Location: The Lake District

    OK I've done some more testing on this issue. I'm certain there is no fault with any of the cards as the exact same thing happened with my last 2 5850s using different bridges. With these Asus cards and with the Powercolour ones I tried 1 bridge and 2 bridges and then swopping bridges around etc, all to no avail.

    I'm pretty sure there is no PSU problem - a healthy Corsair 850w should have more than enough juice for this. Furthermore, it happens even if the CPU and Graphics cards are underclocked. The only solution I've heard of for people who suffer from this, is to flash a 5870 bios and use the Cat 10.5 betas. I don't really want to risk flashing the bios.

    As the cards are only a few days old, I'll return one of them for a refund if I can't fix this. At least it'll fix tessaltion as well as putting £250 in my account.:p
    I've no wish to still be messing around with them when ATI is getting ready to release its next gen cards. :(
     
  14. Jay_t

    Hitman

    Joined: 19 May 2005

    Posts: 714

    Location: The Lake District

    Ok I've finally fixed this issue. I thought I'd post this in case anyone else has this problem. BTW, all my testing was done at stock speed, not the speed in my sig.

    All I did was reverse the position of the 2 cards and everything started working correctly. Just to prove it wasn't a fluke I swopped them back again - and tessellation stopped working once again. Both cards are fine on their own, but it seems only one is capable of being the master card in crossfire.

    I know most of you aren't having this problem, but there are great many who are. I suspect that the QA process does not test for suitability in a crossfire enviroment.
     
    Last edited: 5 May 2010