Maxed Out PCIE Lanes Help

[Guest]

So I am planning on having 2 graphics cards, BUT I have maxed out lanes (16). Now my question: Will it still work if I then add a sound card?

[007agentHP]

yes but one of your gpus will be slowed down to x4.

the impact of that should be limited as PCIE 3.0 x4 should be like PCIE 2.0 x8

[Skiiwee29]

Pretty sure just the GPU's use the CPU PCIe lanes, There are additional lanes on the chipset. Only the graphics card is dedicated to your CPU, so if you add a GPU, you will run in 8x mode on both, which still will not saturate the lanes. All other devices on PCIe pull from the Chipset. 

 

Here is an image based on the B85 chipset you have in your signature.

 

[Electronics Wizardy]

4 minutes ago, 007agentHP said:

yes but one of your gpus will be slowed down to x4.

the impact of that should be limited as PCIE 3.0 x4 should be like PCIE 2.0 x8

Nope, it uses the chipset lanes.

[Electronics Wizardy]

7 minutes ago, jkeasley said:

So I am planning on having 2 graphics cards, BUT I have maxed out lanes (16). Now my question: Will it still work if I then add a sound card?

Also you can't run sli/crossfire on b85, you can only do that on z97/z170/c236/c226

[Guest]

17 minutes ago, legacy99 said:

-snippety-

Oh ok, so I can add another 7 x1 devices to run off the chipset lanes? Or at least another couple, or just one x4?

[Guest]

12 minutes ago, Electronics Wizardy said:

Also you can't run sli/crossfire on b85, you can only do that on z97/z170/c236/c226

Not true, according to the B85-G43 website, it has crossfire support

[Electronics Wizardy]

Just now, jkeasley said:

Not true, according to the B85-G43 website, it has crossfire support

Using the chipset lanes. I said that wrong. You can't spit up the main x16 lanes from the cpu on b85

[Guest]

13 minutes ago, Electronics Wizardy said:

Also you can't run sli/crossfire on b85, you can only do that on z97/z170/c236/c226

Quote

• Multi-GPU: AMD CrossFire Support

Quote from: https://www.msi.com/Motherboard/B85-G43-GAMING.html#hero-overview

[Guest]

2 minutes ago, Electronics Wizardy said:

Using the chipset lanes. I said that wrong. You can't spit up the main x16 lanes from the cpu on b85

What do you mean? If all 4th gen CPUs have 16 lanes and the motherboard says that it supports crossfire, then wouldn't I be able to run crossfire?

[Guest]

Just now, CUDA_Cores said:

You can run crossfire on practically any motherboard. In fact I once did it on a crappy dell OEM machine before and it actually worked. But yeah you are right about the SLI thing Nvidia is much more picky about the boards SLI will work on.

That's why I went for this board, because it supports crossfire. As long as it does that, then I'm fine...right?

[Electronics Wizardy]

Just now, CUDA_Cores said:

You can run crossfire on practically any motherboard. In fact I once did it on a crappy dell OEM machine before and it actually worked. But yeah you are right about the SLI thing Nvidia is much more picky about the boards SLI will work on.

Its intel not allowing you to run 8x 8x from the cpu. only the z97 boards support splitting the main pcie lanes.

[SSL]

Ideally, don't get a souncard regardless.

[DrM]

depending on your budget, its likely to be better getting an external dac. you get less interference noise and it use lanes from the dmi, not the cpu

[Guest]

1 hour ago, CUDA_Cores said:

Why don't you get some sort of USB sound card then. That way you won't be stealing lanes from PCIe. Anyway what cards are you trying to crossfire anyway? It may be worth just selling the old one and buying a new card outright. 

I'm planning 2 secondhand R9 390s

[Guest]

1 hour ago, DrM said:

depending on your budget, its likely to be better getting an external dac. you get less interference noise and it use lanes from the dmi, not the cpu

Dont worry about my budget

[Guest]

1 hour ago, Electronics Wizardy said:

Its intel not allowing you to run 8x 8x from the cpu. only the z97 boards support splitting the main pcie lanes.

All I can say, is that if a motherboard says that I can run crossfire ON B85. Then I can.

[Skiiwee29]

2 hours ago, jkeasley said:

What do you mean? If all 4th gen CPUs have 16 lanes and the motherboard says that it supports crossfire, then wouldn't I be able to run crossfire?

The CPU lanes are dedicated for Graphics cards and their PCI slots. All the other PCIe slots use the Chipset lanes provided and will not affect your graphics PCI Lanes. 

[Guest]

16 hours ago, legacy99 said:

The CPU lanes are dedicated for Graphics cards and their PCI slots. All the other PCIe slots use the Chipset lanes provided and will not affect your graphics PCI Lanes. 

THANK YOU! At least I can get a straight answer from somebody