What a good am3+ MB for crossfire

[simjracer]

hi i need to buy a new am3+ mb due to im going to crossfire to asus radeon hd 7770's but not sure on the specs mainly the PCI Express X modes and i dont want to change any of my parts so i got more cash for the MB

 

[jaquith]

I prefer the AMD 990FX chipset and the Gigabyte GA-990FXA-UD3 is a good choice - http://www.newegg.com/Product/Product.aspx?Item=N82E16813128514 it offers PCIe 2.0 (x16/x16) for CF which is perfectly fine.

 

[simjracer]

hi i need to buy a new am3+ mb due to im going to crossfire two asus radeon hd 7770's but not sure on the specs mainly the PCI Express times modes ( x16 x8 x4) ??? and i dont want to change any of my parts so i got more cash for the MB. i got about £100 and do live in the UK i just like to know what to look for or if any one knows a good MB.

my specs

cpu - amd fx 4170
gpu - asus radeon hd 7770
ram - Kingston 8GB DDR3 1600MHz HyperX Memory (KHX1600C9D3K2/8G)
psu - powercool 750watts
Mb - asrock 960GM-GS3 FX

i was thinking of getting the asrock 970 pro 3 / 970 EXTREME3 / 970 EXTREME4 or 990FX Extreme3
the only reason im picking asrock MB due i know my ram works work with these MB just trying to save money where i can

thanks for any help and it would great full
simon

 

[jaquith]

You only need x8/x8 PCIe 2.0 and even if needed the x4 PCIe 2.0 can work with minimal frame loss; see - http://www.techpowerup.com/reviews/Intel/Ivy_Bridge_PCI-Express_Scaling/ (note: the article was using an Intel IB CPU).

Everything you posted above works on the Gigabyte GA-990FXA-UD3.

So it comes down to budget constraints on the MOBO. The ASRock 990FX Extreme3 would be my choice, again the AMD 990FX chipset is the best choice.