SLI issue(s)

[ALD]

Hiya everyone,

I built a rig recently and my sli option is not showing under nvidia control panel, they're both installed and detected by os; however, primary card working at x16 pcie mode 3.0 and secondary working at x4 pcie mode 1.1! And i have no idea why this happening... i swabbed cards but still same issue...

 

SPECS:

M.B: ASROCK PHANTOM 4

CPU: RYZEN 7  X3700

RAM:64GB G.SKILL DDR4 3000

POWER: SFP AUROM 1000W

GPU: 2X GIGABYTE 2080TI TRIFORCE 

STORAGE: 512 GB NVME X4 PCIE 3.0

                    1TB NVME X4 PCIE 3.0

 

[Acid Panda]

do you have a sli bidge 

or NV link as its now called

[Princess Luna]

Given how the R7 3700X bottlenecks the RTX 2080 Ti at 1080p and 1440p on occasion, SLI'ing two 2080 Ti's will only further cause bottlenecking issues.

 

If you wanted to break the bank with the best you could afford you really should have gone i9 9900K here.

 

Also I just did what you should have done, actually researched about your motherboard (X570 ASROCK PHANTOM 4) and guess what I found out... it does not support SLI, only Crossfire... that's why it won't work.

 

Cheers.

[ALD]

On 10/25/2019 at 1:01 PM, Acid Panda said:

do you have a sli bidge 

or NV link as its now called

Yes i do good sir

[ALD]

On 10/25/2019 at 1:11 PM, Princess Luna said:

Given how the R7 3700X bottlenecks the RTX 2080 Ti at 1080p and 1440p on occasion, SLI'ing two 2080 Ti's will only further cause bottlenecking issues.

 

If you wanted to break the bank with the best you could afford you really should have gone i9 9900K here.

 

Also I just did what you should have done, actually researched about your motherboard (X570 ASROCK PHANTOM 4) and guess what I found out... it does not support SLI, only Crossfire... that's why it won't work.

 

Cheers.

Thank you for your reply!

The board should support sli because the manual that came with it say so, its designed to give crossfire a performance boost but still support sli. Anyway i still don't understand why the master card took all pcie lanes and didn't split it with secondary, does 2080ti needs all 16 lanes to work properly?

Cheers!

[ALD]

On 10/25/2019 at 1:03 PM, Genwyn said:

Your SSD's might not be on PCH lanes and are instead on CPU lanes. Technically you only have 24 actual cpu pcie lanes, so you should be able to do x16 and x8 with the gpus but one of those SSD's is probably using CPU lanes instead of PCH lanes.

 

I would actually suggest removing an SSD first and seeing if you get the right lanes out of the GPUs. If not this can be a weird issue to correct without having good knowledge of that specific boards bios.

Thank you for your reply!

Well there are 24 pcie lanes total, the SSDs' work in ×4 mode so two of them took 8 lanes, the master card took all 16 lanes according to GPU-z, aren't the cpu pcie lanes usually splits when both slots are occupied and if so why is it not happening on my setup??

Cheers!

[ALD]

6 hours ago, Genwyn said:

i could be a whole lot of things, motherboards arent always that great with handing that stuff on the fly, if you havent already, try a bios reset/cmos clear to see if it reassigns the gpus to the slots correctly

 

I'll give it a try, i appreciate your help!