Crossfiring a 6870 with x16 and x4 scaling

I recently got my new motherboard and it's a Gigabyte GA-970-UD3. It says that it have two pci express slots, but one at x16 and one at x4?

I have a 6870 card now and I'm looking to buy another one and crossfire them. Is it worth it? I will be playing BF3, will I max everything out with the crossfire solution at 1680x1050 resolution?

English isn't my native language so please behave, thanks :)
5 answers Last reply
More about crossfiring 6870 scaling
  1. Hello there!
    The actual framerate with 2x HD 6870s @ x16/x4 will be fine, though you will lose a few frames, but nothing significant.
    However, there is a higher chance of microstuttering at that lane setup.

    Here's an example of microstuttering:
    http://www.youtube.com/watch?feature=player_detailpage&v=pw5QZ6NvkIU

    I would just stick with 1 HD 6870 at that resolution,
    You can play the game @ Ultra with around 35FPS average most likely.
    BF3 with HD 6870 Ultra Settings @ 1080p:
    http://www.youtube.com/watch?v=qI4OvHzlga4
  2. If you have 16x/4x, in my opinion it's better when you can sell your old GPU when you get radeon 7xxx series released, then buy a radeon 7xxx that's on your budget :).
  3. AbdullahG said:
    Hello there!
    The actual framerate with 2x HD 6870s @ x16/x4 will be fine, though you will lose a few frames, but nothing significant.
    However, there is a higher chance of microstuttering at that lane setup.

    Here's an example of microstuttering:
    http://www.youtube.com/watch?feature=player_detailpage&v=pw5QZ6NvkIU

    I would just stick with 1 HD 6870 at that resolution,
    You can play the game @ Ultra with around 35FPS average most likely.
    BF3 with HD 6870 Ultra Settings @ 1080p:
    http://www.youtube.com/watch?v=qI4OvHzlga4


    I have read a review about this x16 combined with x4 with a 5870 crossfire setup. It said that you only lose like 4-5% fps?
  4. But since the 7xxx series are coming out, it'll be better to you, because you will have less issues and better performance compared t your current graphics card.
  5. veb95 said:
    I recently got my new motherboard and it's a Gigabyte GA-970-UD3. It says that it have two pci express slots, but one at x16 and one at x4?

    I have a 6870 card now and I'm looking to buy another one and crossfire them. Is it worth it? I will be playing BF3, will I max everything out with the crossfire solution at 1680x1050 resolution?

    English isn't my native language so please behave, thanks :)



    In regards to 16x 4x pci-e lanes, have a look here.

    http://www.youtube.com/watch?v=rSfifE2Domo&feature=youtu.be

    This answered a question I had in another topic about the same issue I have with a 6990 and two 6970's. According to this test, running a high end 6990 at 16x 8x or 4x was a difference of less than 200 points over all on a score of x3300 roughly. I would say based on that, you are looking at a 1% difference due to the 4x slot. I have no experience with that card but adding another in crossfire will be a hell of a lot cheaper than starting over with a new gpu and I bet you will get pretty good fps also.
Ask a new question

Read More

Graphics Cards Crossfire Graphics