New build not recognizing SLI

[Drez]

All, I'm in a bit of a jam here and I'm not sure what to do. Any advice is greatly appreciated. I just did a brand new build and it looks like my rig is not recognizing my 2nd card.

 

My Build:

 

Windows 10 Home

i7 6700

Asus z170-a mobo

SLI MSI 980ti Armor 2x

 

 

What I've done so far:

 

Updated nvidia drivers to 359 (latest driver)

Flashed the BIOS on my Asus z170-a to the latest version

Tried each card individually and they worked

Checked and rechecked connections and everything appears fine

 

Here's what I've noticed:

 

Monitors work fine on top card but don't work in the 2nd card in the 3rd slot of the mobo. I don't think it's the card, could the 3rd slot in the mobo be bad?

 

Checked the BIOS and it doesn't even detect that there's a second card plugged in.

 

I have an MSI SLI bridge that lights up when the power comes on if that means anything?

 

Could the mobo be bad?

 

I hope this gives some kind of information. Please, any and all help is greatly appreciated. This is my first build on my own and I'm becoming a bit disheartened. Thank you in advance for your help.

[Godlygamer23]

If you can get another bridge to use, maybe from a friend, that would be swell.

[airdeano]

either the power to the second GPU isn't connected properly, the PCIe slot is

dead, GPU is bad or CPU pin to PCIe slot is not making proper connection.

 

remove dead card, reboot. swap GPUs and reboot (if POST is good then you

have mobo/power/CPU issues)

 

register your mobo and then open a tech support ticket about your issue.

[Drez]

If you can get another bridge to use, maybe from a friend, that would be swell.

I have the stock standard Asus SLI bridge and I tried that.  Same results.

 

 

either the power to the second GPU isn't connected properly, the PCIe slot is

dead, GPU is bad or CPU pin to PCIe slot is not making proper connection.

 

remove dead card, reboot. swap GPUs and reboot (if POST is good then you

have mobo/power/CPU issues)

 

register your mobo and then open a tech support ticket about your issue.

I've swapped the cards, tried them one by one, still same thing.  Each one individually works, I've tested that.  So I know it's not the GPU's themselves.  I guess I'll just open a ticket with Asus and see where that goes.  Thank you both for your help.

[Nemesis109]

You said monitors? So you have more than one? If you do both monitors need to be plugged into the same gpu.

http://www.nvidia.in/object/sli-technology-multimonitor-in.html

 

In the SLI option are both cards showing up in Nvidia control panel under configure SLI, surround, PhysX?

[Drez]

There's no mention of anything SLI in the nvidia control panel. Both monitors are plugged into the top card.

[airdeano]

the tip was the 2nd GPU no showing up in the UEFI. if powered and signal from

slot was clear, it'd show up in the UEFI. the slot is not getting to CPU via bad slot,

damaged trace or CPU socket issues.

[Nemesis109]

Is there any particular reason you are using the 3rd slot and not slot 1 & 2? Have you tried not using the 3rd slot to eliminate that as the problem?

 

Also 980ti use quite a bit of power Is the PSU you are using high enough wattage? And also are the power connectors on separate rails if possible to ensure there is enough power getting to both cards?

[Godlygamer23]

I can tell you what the problem is. It is a technical limitation of the slot itself. On ASUS website, it states it runs at x4. NVIDIA requires SLI to have at least x8 regardless of slot generation.

 

I'm referring to the bottom PCIe slot by the way. The bottom card needs to get shifted up to the top.

Specs: https://www.asus.com/us/Motherboards/Z170-A/specifications/

[Godlygamer23]

the tip was the 2nd GPU no showing up in the UEFI. if powered and signal from

slot was clear, it'd show up in the UEFI. the slot is not getting to CPU via bad slot,

damaged trace or CPU socket issues.

The UEFI won't acknowledge multiple cards I don't think.

[Drez]

I think I found the problem. I unplugged 3 of the 4 memory sticks and all the HD's and then the bios recognized the end card. So apparently my 850 isn't pumping enough juice. Just picked up a 1300w version of my PSU. I'll post back here once I have it in.

Thank you everyone for all the help so far. It's greatly appreciated.

[Godlygamer23]

I think I found the problem. I unplugged 3 of the 4 memory sticks and all the HD's and then the bios recognized the end card. So apparently my 850 isn't pumping enough juice. Just picked up a 1300w version of my PSU. I'll post back here once I have it in.

Thank you everyone for all the help so far. It's greatly appreciated.

I don't think the power supply is the issue - I'm pretty sure you wasted your money purchasing a 1300W power supply. 980 Ti's in SLI pull 587W.

http://www.techspot.com/review/1033-gtx-980-ti-sli-r9-fury-x-crossfire/page6.html

 

In that review, Techspot was using a 5960X which pulls more power.

[Drez]

The cards are in the first and second pci-e slots.

The PSU swap didn't work. Asus had me reset the bios and cmos and that didn't work. I put the msi sli bridge on and it detected both cards, but when doing benchmarking it only detected one card. I tried putting the Asus sli bridge back on and now the bios isn't detecting both cards. Swapped it back and same thing, still not detecting it. Could I just have a bad mobo?

[Drez]

Turns out it was a defective custom braided GPU cable from the card to the powersupply.  Replaced it with a stock cable and it now detects the second card and SLI is working.  Appreciate everyones help. 

[airdeano]

congrats on the repair.. knew it was s'mthin' simps..

[Drez]

Yeah glad it was something simple.  I spent about an hour on the phone with ASUS before they just told me to RMA the motherboard back since it was bad     Oh well.  Definitely got some good troubleshooting skills in this weekend.  Thanks again for the help.