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7870 crossfire on PCIE 2.0/Z68 perfomance hit???

Hi Guys,

I am helping out a friend and building a PC for him next weekend.

We are sticking to a Sandy bridge build and we have all the components set up. Here is the configuration we are looking at:
i7 2600K
Gigabyte GA-Z68XP-UD3R 32GB DDR3
Corsair 8GB
Sapphire 7870 OC edition 2GB
Corsair HX 650
Corsair H100 ( Black)
Corsair 500R
Corsair Nova 60 GB SSD

I have highlighted the motherboard because of a couple of things. We are a bit concerned about her. The reasons we are looking at that board is:
- Its black and matches our overall build. Aesthetics are VERY important.
- 2 PCIE 2.0 slots running at X16 or X8/X8
- Overclocking

Now, the problem I am reaching out to you guys is because we obviously want 2 PCIE slots so that we can add a second card later a year or so later. But, the main question is will a PCIE 2.0 board reduce crossfire performance for compared to a PCIE 3.0 board?

I was looking at a couple of threads and am well aware that lanes do not saturate. Picture link below.

http://images.hardwarecanucks.com/image//skymtl/GPU/HD7970/HD7970-68.jpg

But I have also read that the 7970 on a Z68 is taking a 10-15% hit in performance somewhere recently. I cant find the article anymore. :-(

Pricing is critical and I cant buy a better board for the chap and he needs a 2600K in his build for rendering. The GPU is also set as we are getting a sweet deal via a friend.

Will cross firing hit our performance in the future? Or will we have to kill something and buy a more expensive Z77 board?

Any advice would be helpful. Cheers!!!!
6 answers Last reply Best Answer
More about 7870 crossfire pcie perfomance
  1. Also, correct me if I am wrong.

    But PCIE 3.0 = 2 x PCIE 2.0

    So does that mean that a PCIE 3.0 x4 = PCIE 2.0 x 8 right? Does this mean that even crappy entry level Z77 boards will have the same performance as a say, Z68 x8/x8 board?

    Damn....
  2. You just answered your question by providing the link.
    Anyway
  3. Best answer
    Performance hit caused by older PCIE generation 1.1 and also the X4 speed, anything else doesn't affect the performance
  4. Here's another good thread.

    http://www.evga.com/forums/tm.aspx?m=1537816&mpage=2&print=true

    Pheww...So basically 3.0 is a scam.
  5. Best answer selected by mailpranshu.
  6. Thanks a lot mate...

    Closing out the thread.
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