No SLI option in nvidia control panel on dual 1080 ti

[Sleroy0714]

I set up dual evga 1080ti FTW3 in my new setup and noticed that I dont have the option of SLI configuration in nvidia control panel.

Both my GPU's are visible on my system.

In Nvidia experience I have the latest drivers.

I've also installed a SSD adapter on a in a PCie slot, which is also running properly.

When in Evga precision, my master card is running on full frequency and my slave card is at idle. 

I've tried finding information on my motherboard and how is supports populated PCie slots but I can seem to find much on my specific scenario. 

 

Anyone have any suggestions or possible solutions? 

 

 

[jones177]

I had that happen today.

I turned the bridge around and it worked.

Now the writing on the bridge is upside down.

 

Once you get it working you will be amazed.

 

[Sleroy0714]

Thanks jones177 for the tip I tried it out and it made no difference for me.

Although I went into my bios and changed PCIEX16/x8_1 mode to GEN 1 instead of Auto and changed my M.2_2 PCie Bandwidth to Auto instead of (Disable (X4/X4 mode)) and it seemed to have the SLI configuration option when I started up.

[Mick Naughty]

Just seems like the second card was running at 4x then. Main concern when it comes to taking lanes from the gpus. 

[GamerDude]

2 hours ago, Mick Naughty said:

Just seems like the second card was running at 4x then. Main concern when it comes to taking lanes from the gpus. 

That's my thought as well, SLi doesn't play nice with 4x

[Sleroy0714]

5 hours ago, Mick Naughty said:

Just seems like the second card was running at 4x then. Main concern when it comes to taking lanes from the gpus. 

Im not very clear with what settings I achieve on PCie x16/x8 mode being at gen 1,  gen 2 or gen 3.

Would gen 1 be using x16/x8, gen 2 would be x8/x8 and gen 3 x8/x4?

[Mick Naughty]

18 minutes ago, Sleroy0714 said:

Im not very clear with what settings I achieve on PCie x16/x8 mode being at gen 1,  gen 2 or gen 3.

Would gen 1 be using x16/x8, gen 2 would be x8/x8 and gen 3 x8/x4?

Well it being short for generation, 3 should be 16. But even if you chose something different, populating certain slots wild over ride that. Gen 1=4x, gen2 8x and 3 is 16. You pick for each slot too. If applicable. 

 

I have mine set to gen 3 on all of my boards if they aren’t on auto but my second slot couldn’t run at 16 anyway. Most don’t have the actual pins. 

[Sleroy0714]

1 hour ago, Mick Naughty said:

Well it being short for generation, 3 should be 16. But even if you chose something different, populating certain slots wild over ride that. Gen 1=4x, gen2 8x and 3 is 16. You pick for each slot too. If applicable. 

 

I have mine set to gen 3 on all of my boards if they aren’t on auto but my second slot couldn’t run at 16 anyway. Most don’t have the actual pins. 

 I changed it to gen 3 and wow what a difference, thanks! I was starting to get discouraged that I I was capping out even though I had my v sync settings on fast. I noticed that I don't have the option to change the settings for PCie x8/x4_2 slot is that normal? When I put it to PCie x16/x8 mode to gen3 is it already changing PCie x8/x4_2 slot to x8?

[Mick Naughty]

Just now, Sleroy0714 said:

 I changed it to gen 3 and wow what a difference, thanks! I was starting to get discouraged that I I was capping out even though I had my v sync settings on fast. I noticed that I don't have the option to change the settings for PCie x8/x4_2 slot is that normal? When I put it to PCie x16/x8 mode to gen3 is it already changing PCie x8/x4_2 slot to x8?

Prolly because the board cant do anything aside from that. The cards will run 8x/8x. So Only way to make it work unless you have a nice board and a lot of lanes to have both cards run at 16x/16x and still have lanes left over for m.2s and such. 

[Sleroy0714]

5 minutes ago, Mick Naughty said:

Prolly because the board cant do anything aside from that. The cards will run 8x/8x. So Only way to make it work unless you have a nice board and a lot of lanes to have both cards run at 16x/16x and still have lanes left over for m.2s and such. 

From what I'm understanding I'm running x8/x8 on both my PCie slots and a x4 on my bottom PCie slot? why do I have x16/x8 mode in my bios then?

[Mick Naughty]

Just now, Sleroy0714 said:

From what I'm understanding I'm running x8/x8 on both my PCie slots and a x4 on my bottom PCie slot? why do I have x16/x8 mode in my bios then?

Because its an option. Doing sli, they have to be the same. So you can have 16x but it isn't gonna run that unless what ever is in that slot runs independent. 

[Sleroy0714]

I get what you're saying. I don't see that there's an AM4 socket MB with dual or triple PCie x16/x8 slots. Is that possible?

[Mick Naughty]

Idk about that socket but I don’t see why you would want triple 8x 

[Ebony Falcon]

4 hours ago, Sleroy0714 said:

I get what you're saying. I don't see that there's an AM4 socket MB with dual or triple PCie x16/x8 slots. Is that possible?

Think u need to look at boards with plexy chips but I don’t no a great deal about them

[Sleroy0714]

15 hours ago, Ebony Falcon said:

Think u need to look at boards with plexy chips but I don’t no a great deal about them

I have my 2 GPU's using 8 lanes each and my M.2 SSD is using the last 4 lanes which is the most my CPU can handle. I took a look at PLX chips and from what I understood it wont make a difference on my rig because my CPU is limited to 20 lanes. PLX is on a MB that accepts chips with higher lanes, that's why AM4 boards don't have more PCie slots or PLX chips because those types of CPU's aren't designed with more than 20 lanes.

[Mick Naughty]

What are you needing more lanes for?

Some boards have some pci slots handled by the chipset if no plx chip.

[Sleroy0714]

Just now, Mick Naughty said:

What are you needing more lanes for?

Some boards have some pci slots handled by the chipset if no plx chip.

I don't need more lanes. I wanted my GPU's and M.2 SSD on my PCie adapter to be running as fast as possible. My research says the SSD only needs 4 lanes and I don't have the amount of lanes on the CPU or MB to have the two GPU's both on 16x like I thought in my head. It's my first rig I've built so I'm new to all this and just figuring everything out.  

[Mick Naughty]

8 minutes ago, Sleroy0714 said:

I don't need more lanes. I wanted my GPU's and M.2 SSD on my PCie adapter to be running as fast as possible. My research says the SSD only needs 4 lanes and I don't have the amount of lanes on the CPU or MB to have the two GPU's both on 16x like I thought in my head. It's my first rig I've built so I'm new to all this and just figuring everything out.  

Does your board support 16x on the second slot? What difference do you think gen 3 8x is losing from 16x? Those aren't titan v's right?

[Sleroy0714]

2 minutes ago, Mick Naughty said:

Does your board support 16x on the second slot? What difference do you think gen 3 8x is losing from 16x? Those aren't titan v's right?

My second slot only supports 8x at most. My GPU's are GTX 1080 Ti's. I'm already picking up way more FPS since I went from one 1080ti to two 1080ti's so I not complaining having my cards at x8/x8. I thought I was able to have both at 16x but I only now understood the whole concept of lanes on PCie slots and the CPU. If I used an intel CPU with more lanes and a board that had 16x on the second PCie slot would it have a dramatic difference over my set up?

[Mick Naughty]

1 minute ago, Sleroy0714 said:

My second slot only supports 8x at most. My GPU's are GTX 1080 Ti's. I'm already picking up way more FPS since I went from one 1080ti to two 1080ti's so I not complaining having my cards at x8/x8. I thought I was able to have both at 16x but I only now understood the whole concept of lanes on PCie slots and the CPU. If I used an intel CPU with more lanes and a board that had 16x on the second PCie slot would it have a dramatic difference over my set up?

Not really, one of those cards cant saturate a 16x lane. So the gains would be minimal if any. And a board that can run both slots at 16x wouldn't be cheap. Also wouldn't be worth it. But if you wonna spend the cash to find out, by all means.

[Sleroy0714]

1 minute ago, Mick Naughty said:

Not really, one of those cards cant saturate a 16x lane. So the gains would be minimal if any. And a board that can run both slots at 16x wouldn't be cheap. Also wouldn't be worth it. But if you wonna spend the cash to find out, by all means.

I figured it couldn't use up the full 16 lanes to get a substantial difference. My rig is preforming great and I just finished it is so I'm not looking to change it just yet. It's simply to know for the future if I decide to change to an intel chip with more lanes and find something more budget wise or upgrade/ invest into a threadripper for the performance.