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Microstuttering experiment with 7950 Crossfire, use two bridges instead of one.

Discussion in 'AMD / ATI' started by Ephremius, Jun 21, 2013.

  1. Ephremius New Member

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    I am using 2 CF bridges instead of one for my 7950 x2 setup... and games do seem a little smoother... has anyone done real world tests on this to compare and contrast 1 vs 2 bridges?
     
  2. MxPhenom 216

    MxPhenom 216 Corsair Fanboy

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    I asked this years ago, and was told it didn't make much of a difference between 1 and 2 bridges.
     
  3. freaksavior

    freaksavior To infinity ... and beyond!

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  4. cadaveca

    cadaveca My name is Dave

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    That's from a bit overt 2 years ago, and drivers have changed so much that this is a question worth asking again. The whole "ask google" things is getting really old, BTW. Sometimes people would like a conversation about a subject to answer questions, or just sort things out in their head. The only dumb questions are those not asked. :)


    However, personally, I see ZERO difference. I could grab a second card off my shelf and check it again, but I don't have matched pairs now, just 7970 and 7950. Waiting for my second 7970 to be returned from being out on loan.
     
  5. drdeathx

    drdeathx

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    OMG, we will give you a pass..... this is why the club exists. I am sure OP appreciates it though/
     
  6. erocker

    erocker Super Moderator Staff Member

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  7. Ephremius New Member

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    Thanks Cadaveca, I agree with you in full.

    I will try some testing with one and two bridges, thanks for the link erocker.
     
  8. theoneandonlymrk

    theoneandonlymrk

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  9. m1dg3t

    m1dg3t

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    Anyone looking forward to the 31st of July, IIRC? Supposedly AMD/ATi will be releasing the new Catalyst package that sorts out the CF/X issues that people have been complaining about...

    Hopefully they did manage to sort it out :)
     
    antony209494 and Ephremius say thanks.
  10. Ephremius New Member

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    I read about this on Guru 3D as well Midget. I can't wait.
     
  11. m1dg3t

    m1dg3t

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    I came across something about it over @ XtremeSystems i think :confused:

    Since i built this iTX rig i've been tempted to run a dual GPU card and ATi is my preferred GFX so i been holding off. I was really looking forward to what the 7990 was to bring but :(

    I prolly wouldn't have picked it up at or near release anyways but still was curious/hoping for a good solution. My idea is to bump the 7950 into my 775 rig and pass the 5870 along to my uncle for his FlightSIM box and pop a dual GPU into the Prodigy. That should keep me going for the next few years... *Should* :laugh:

    I usually keep CPU/MoBo for a while and add RAM if needed and upgrade GFX as required, since i only game those are the important pieces. For me.

    :toast:
     
  12. Ephremius New Member

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    Same for me Midget, all I do is game I mean. I think my 7950 CF at 1200/1500 is going to last me several years still, especially since the next gen consoles will be porting more AMD optimized games for the next 5 or so years at least. Regardless, when Skylake CPU and DDR4 ram comes out, I may do a complete overhaul, not sure yet. I really don't even see total war rome 2 later this year destroying my 7950 cf setup, sure I may have to turn off shadows, but I could care less about shadows. :roll:
     
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  13. m1dg3t

    m1dg3t

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    Your CPU would be the "weak link" before your GFX, IMHO, providing you don't move into high res/refresh monitors. Even then, ATi handles high res Ok. I'd eventually like to step into a 120Hz monitor as well, so that is part of it, but thinking thia all wont happen untill a year or so goes by :eek:

    :toast:
     
  14. antony209494

    antony209494

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    From my limited experience, I also have to agree that using a second bridge makes no difference. I had about 3 crossfire rigs and I was always trying one and two bridges but I never noticed any gains.
     
  15. erocker

    erocker Super Moderator Staff Member

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    Me too except for a pair of 4890's that I had. They didn't like not having two for some reason.
     
  16. antony209494

    antony209494

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    I have set my next GPU update to Volcanic Islands (HD 9 series). Till then the 6970/6950 CF will hold :D
     
  17. qubit

    qubit Overclocked quantum bit

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    I'm not really surprised that adding a second bridge makes no measurable difference. In fact, I'll go as far as to say that the second connection is likely disabled.

    Think about it: AMD will have designed the crossfire bridge to carry all the signals and bandwidth that it requires to work and there's nothing in the documentation to say about connecting a second one. Hence, the second one should make no difference and doesn't in benchmarks.

    Also, I agree with letting people talk about a subject, even if it's answered elsewhere. If nothing else, it can add a different perspective to it as people think of different angles.
     
  18. erocker

    erocker Super Moderator Staff Member

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    My 4890's say differently... I have no idea why though. :laugh:
     
  19. antony209494

    antony209494

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    Although I agree, there is actually documentation (board manuals mostly) that specify the use of two bridges on dual crossfire setups.
     
  20. qubit

    qubit Overclocked quantum bit

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    Hey, lol. What difference do you see?

    Is that specific to certain card generations, I wonder?
     
  21. antony209494

    antony209494

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    I don't know. But I remember that my old board manual in the CF setup instructions said "both bridges should be connected" as if it's a requirement for CF to work :laugh::laugh::laugh:
     
  22. james888

    james888

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    Why not just connect with two. They come with two anyways.
     
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    Crunching for Team TPU
  23. qubit

    qubit Overclocked quantum bit

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    Sometime those mobo manuals are quite wrong and it looks like this was one of those times. If the cards needed it, then there's no way AMD wouldn't mention it.
     
  24. cadaveca

    cadaveca My name is Dave

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    AMD's driver itself (CURRENTLY) will tell you to connect BOTH bridges when none are connected. But you aren't an AMD GPU user, so I'm not sure why you are even offering info, because you'd have no idea that that was the case. :p

    That's why I made the first comment I did in this thread. The driver tells you to connect both. Why? I dunno.

    I've actually been waiting for someone to bring up this topic, since I saw this many times in the past 6-8 months.
     
  25. erocker

    erocker Super Moderator Staff Member

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    1 bridge = Insane flicker-fest

    2 bridges = Happy gamingz!
     

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