PCIe 2.0 Bottleneck

[kev507]

I'm planning to build an all-AMD themed computer, but here's my question:

 

Will crossfire R9 290X's bottleneck when running at PCIe 2.0 16x/8x on the ASUS Crosshair V Formula Z? One of those cards would essentially be running at the same bandwidth as PCIe 3.0 4x which worries me, especially because those cards are also doing crossfire over the PCIe bus instead of over a separate bridge. As a current intel owner, I have always been told that you should not do 3 way crossfire or SLI on PCIe 3.0 8x/8x/4x because PCIe 3.0 4x will bottleneck the system.

[Cacao]

What CPU do you have? If you're still on PCIe 2.0 chances are your CPU will also bottleneck 2x 290x.

[kev507]

I'm planning on using the 9590, so limited/no bottleneck there

[kev507]

oops, i misread the specs, forget I asked anything. This board runs 16/8/8 or 16/16

[The Crazed Child]

PCI-E 2.0 will not provide a discernible bottleneck especially in 16x mode. Go for it!

[Bagmup]

oops, i misread the specs, forget I asked anything. This board runs 16/8/8 or 16/16

I was gonna say, nearly all PCI 2.0 asus boards anyway, run @16/16 in crossfire.

[Analog]

There will be no bottleneck. Both of the cards will run fine. Have already bought that processor? The FX 9590 is a complete waist of money, since it's essentially a highly overclocked FX 8320. If you haven't bough it yet, you can easily get the cheaper FX 8320 and a decent  AIO liquid cooler and overclock that to 5GHz. Something like the Swiftech H220, H320 and the Corsair H110 are great options for AIO liquid coolers. 

 

PS: You will need one of those coolers to run the FX 9590 anyway. 

[harrynowl]

Hmm. 

 

I think you'd be better off just going Intel instead of the 9590.

 

In some games it will bottleneck (the ones that only use a couple cores).