x16 and x8 CrossFirex

[timtheman678]

Hello, I have a MSI 970A G46. I have two 7950's and I am wondering if I am going to see much of a performance decrease when I use a combination of x16 and x8 in a CrossFire configuration. according to this video by Linus (http://www.youtube.com/watch?v=NFMzRZqFh-w) I only see a 3 point increase in X points in 3DMark Vantage. But that is a synthetic benchmark so I am wondering if I will actually see a decrease in performance when gaming. Thanks!

 

[WarWolverineWarrior]

none. Technically 8x is all you need. so 2x8lanes is good.

only Dual GPUs use full 16 lanes aka 7990

7970 and lower use half of the bandwith so 8 lanes is all you need for a card. PCIe 2.0 at least

 

[timtheman678]

Yes, but this is a combanation of x8 and x16.

 

[bigpinkdragon286]

I'm running a x16 and x4 configuration in one system, and it works just fine. The bandwidth requirements of non-top tier cards is generally well below what most slots provide.

 

[WarWolverineWarrior]

I'm running a x16 and x4 configuration in one system, and it works just fine. The bandwidth requirements of non-top tier cards is generally well below what most slots provide.

Nvidia drivers seem to handle that better than AMD

 

[bigpinkdragon286]

NVIDIA may handle the situation better, but it is a pair of 7870 LE cards that I have in the x16 and x4 configuration. The performance of the cards are very near the performance of the cards which the OP was asking about.