sli PCIe 3.0 x16/x16 or is x16/x8 just as good? Need help picking motherboard

fyodor1917

Honorable
Jun 21, 2013
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10,510
I'm looking to buy a mobo that has two PCIe 3.0 x16 slots so that I can add a second GPU in the future and get the most out of it.

However what I have found is either motherboards that have one 3.0 x16 and one 3.0 x8 or two 3.0 x16 slots but these always seem to suggest in the description that once you actually plug in a second GPU it actually treats it like two x8 slots (or one is one x16 and the second x8?)

Specifically i am looking at these two motherboards because they are part of a cpu combo deal at the moment

This one has 3.0 x16 and a 3.0 x8:
http://www.newegg.com/Product/Product.aspx?Item=13-128-592

This one has two 3.0 x16 slots but, like I said, seems that you cannot actually use two GPUs at x16:
http://www.newegg.com/Product/Product.aspx?Item=13-157-371
 
Solution
As of right now, there are very few if any graphics cards that could fully saturate a PCIe 2.0 x16 slot (we're talking gtx 690s and HD 7990s), and even those don't get there. As PCIe 3.0 is twice as fast, the previous statement is true for PCIe 3.0 x8 slots. There will be no real-world difference between using x16 and x8 on PCIe 3.0 slots.

xcrossroadsx

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Dec 13, 2011
247
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18,860
As of right now, there are very few if any graphics cards that could fully saturate a PCIe 2.0 x16 slot (we're talking gtx 690s and HD 7990s), and even those don't get there. As PCIe 3.0 is twice as fast, the previous statement is true for PCIe 3.0 x8 slots. There will be no real-world difference between using x16 and x8 on PCIe 3.0 slots.
 
Solution