SLI 1080s stuck at 8x and 2x

[H20Burner]

I do have a m.2 drive. Took it out with same results. Disabled the wifi and bluetooth controllers. Same results. Board is Asus maximus x formula z370, CPU - 8086k. Any suggestions?

[Crunchy Dragon]

Are the GPUs in the topmost PCIe x16 slots?

[H20Burner]

Just now, Crunchy Dragon said:

Are the GPUs in the topmost PCIe x16 slots?

Yes. And those slots are also asus recommended.

[Mick Naughty]

You reseat the cpu? May need to default the bios or flash it. Are you using gpuz to see the lanes or the bios? Could try reseating the cards as well. 

[H20Burner]

8 hours ago, Mick Naughty said:

You reseat the cpu? May need to default the bios or flash it. Are you using gpuz to see the lanes or the bios? Could try reseating the cards as well. 

Cards and cpu were reseated. Bios was defaulted/updated, same problem.

[Mick Naughty]

Just now, H20Burner said:

Cards and cpu were reseated. Bios was defaulted/updated, same problem.

So what does it do with one card in each slot?

[H20Burner]

1 minute ago, Mick Naughty said:

So what does it do with one card in each slot?

What do you mean by 1 card in each slot. Yea each card gets its own slot.

[Mick Naughty]

Just now, H20Burner said:

What do you mean by 1 card in each slot. Yea each card gets its own slot.

As in what do they read in each slot by themselves.

[H20Burner]

1 minute ago, Mick Naughty said:

As in what do they read in each slot by themselves.

8x and 2x

[Mick Naughty]

Just now, H20Burner said:

8x and 2x

Jesus, what does each card do, by itself, in each slot. As in one card in the pc at a time, tested in each slot.

[H20Burner]

1 minute ago, Mick Naughty said:

Jesus, what does each card do, by itself, in each slot. As in one card in the pc at a time, tested in each slot.

Ohh sorry. Ill test them rn.

[H20Burner]

17 minutes ago, H20Burner said:

Ohh sorry. Ill test them rn.

K. 4x with single card. @Mick Naughty

[Mick Naughty]

21 minutes ago, H20Burner said:

K. 4x with single card. @Mick Naughty

So can you change it in the bios? Set it gen3, also what are you doing to verify the speed?

[H20Burner]

2 minutes ago, Mick Naughty said:

So can you change it in the bios? Set it gen3, also what are you doing to verify the speed?

No. It is set to gen 3. I am using asus gpu post in the bios.

[-rascal-]

2 hours ago, H20Burner said:

8x and 2x

 

1 hour ago, H20Burner said:

K. 4x with single card. @Mick Naughty

 

The M.2 drive should not interfere with the two main PCI-E slots where the video cards install into.

 

If one card is connected to the top PCI-E X16 slot, you SHOULD be seeing X16 mode (X16 + X0).

If you use both slots, then the top slot becomes X8, and the second slot becomes X8 (X8 + X8).

 

You seeing 8x in the top slot is correct.

Seeing 2x and 4x is NOT correct.

 

Are you seeing 4x when only ONE GTX 1080 is installed in the top slot (second card not installed)?

 

I would recommend that you check the CPU socket for any bent or damaged pins.

[H20Burner]

On 7/30/2018 at 3:36 PM, -rascal- said:

 

 

The M.2 drive should not interfere with the two main PCI-E slots where the video cards install into.

 

If one card is connected to the top PCI-E X16 slot, you SHOULD be seeing X16 mode (X16 + X0).

If you use both slots, then the top slot becomes X8, and the second slot becomes X8 (X8 + X8).

 

You seeing 8x in the top slot is correct.

Seeing 2x and 4x is NOT correct.

 

Are you seeing 4x when only ONE GTX 1080 is installed in the top slot (second card not installed)?

 

I would recommend that you check the CPU socket for any bent or damaged pins.

Correct.I am seeing 4x in the first slot with 1 gpu installed. Will do. I will post back here results.

 

-Edit: No bent pins found.

[-rascal-]

18 hours ago, H20Burner said:

Correct.I am seeing 4x in the first slot with 1 gpu installed. Will do. I will post back here results.

 

-Edit: No bent pins found.

 

That is a problem...

You are getting only 1/4th of the lanes when one GPU is installed.

 

Do you see any damage in the two PCI-E slots?

Are you able to upload a picture(s) of the two main PCI-E X16 slots?

What about the PCI-E X16 connector/pins on the video card, any dirt or damage on those?

 

I'll have to check the motherboard documents, and see what else could be causing this issue.

[dalekphalm]

18 hours ago, H20Burner said:

Correct.I am seeing 4x in the first slot with 1 gpu installed. Will do. I will post back here results.

 

-Edit: No bent pins found.

Do you have any other motherboards handy that have PCIe Gen 3? (Even if it's a family or friend)

 

If so, pop each GPU - one at a time - into the other motherboard and verify that it's running at x16.

 

My bet is a bad motherboard or bad CPU.

[-rascal-]

23 minutes ago, dalekphalm said:

Do you have any other motherboards handy that have PCIe Gen 3? (Even if it's a family or friend)

 

If so, pop each GPU - one at a time - into the other motherboard and verify that it's running at x16.

 

My bet is a bad motherboard or bad CPU.

 

Agreed.

 

Doesn't need to be a motherboard with PCI-E Gen3 -- Gen2 should be fine -- just need to make sure it's showing X16 lanes with the GPU installed.

[dalekphalm]

1 hour ago, -rascal- said:

 

Agreed.

 

Doesn't need to be a motherboard with PCI-E Gen3 -- Gen2 should be fine -- just need to make sure it's showing X16 lanes with the GPU installed.

True - but I figured an "Apples to Apples" comparison would eliminate more variables.

[-rascal-]

Oh @H20Burner is your CPU overclocked by any chance.

If so, did you increase the BCLK, or just the CPU multiplier/ratio?

 

Slo-mode is not accidentally enabled?

There's a physical switch at the bottom of the motherboard (page 1-12 of motherboard manual)

 

LN2 mode jumper is at the disabled position?

(page 1-14 of motherboard manual)

[H20Burner]

12 hours ago, -rascal- said:

 

That is a problem...

You are getting only 1/4th of the lanes when one GPU is installed.

 

Do you see any damage in the two PCI-E slots?

Are you able to upload a picture(s) of the two main PCI-E X16 slots?

What about the PCI-E X16 connector/pins on the video card, any dirt or damage on those?

 

I'll have to check the motherboard documents, and see what else could be causing this issue.

No. Not any damage that I can see. No the pins on the gpu are good.

12 hours ago, dalekphalm said:

Do you have any other motherboards handy that have PCIe Gen 3? (Even if it's a family or friend)

 

If so, pop each GPU - one at a time - into the other motherboard and verify that it's running at x16.

 

My bet is a bad motherboard or bad CPU.

None of them will run at 16x. My last board these 1080s were on had it on 8x/4x. It was x99.

 

5 hours ago, -rascal- said:

Oh @H20Burner is your CPU overclocked by any chance.

If so, did you increase the BCLK, or just the CPU multiplier/ratio?

 

Slo-mode is not accidentally enabled?

There's a physical switch at the bottom of the motherboard (page 1-12 of motherboard manual)

 

LN2 mode jumper is at the disabled position?

(page 1-14 of motherboard manual)

 No I never overclock by blck. I only add voltage. Its only a 100mhz oc anyway. Slow switch is off. And ln2 mode is also off too.

[Guest]

4 minutes ago, H20Burner said:

None of them will run at 16x. My last board these 1080s were on had it on 8x/4x. It was x99.

Test the cards one at a time in your spare setup. 

 

I'm also not sure that the processors (they do control) have differing PCI-e lanes on this sku. Would have to check, but this is probably a motherboard issue. You could try using a different card to check the slot as well, maybe borrow a friends or pop into freegeek - any PCI-e graphics card should be able to run at x16. 

[H20Burner]

4 minutes ago, RorzNZ said:

Test the cards one at a time in your spare setup. 

 

I'm also not sure that the processors (they do control) have differing PCI-e lanes on this sku. Would have to check, but this is probably a motherboard issue. You could try using a different card to check the slot as well, maybe borrow a friends or pop into freegeek - any PCI-e graphics card should be able to run at x16. 

I don't have a spare setup atm. I sold the old board and cpu to chip into this new one. Ill ask a friend.

[H20Burner]

I think i'm gonna ride out the performance loss. I will be getting 2x xx80 ti when they come out. I will be selling these 2 current cards for $400 a pop so I get 1 "theoretically" 1 "free" xx80 ti.