cancel
Showing results for 
Search instead for 
Did you mean: 

Trouble Recognizing Two Nvidia GTX 980 Ti's

eranostal
Level 7
I figured I would give this a shot, since at this point I'm kinda completely at a loss as to why this isn't working.

I recently purchased a Maximus VII hero for a new rig I built: specs below.


  • ASUS Maximus 7 Hero ATX LGA1150 Motherboard
  • BIOS Update 3003
  • Intel Core i7-4790K 4.0GHZ Quad-Core Processor
  • Corsair Vengeance 16GB (4x4GB) DDR3-2133 Memory
  • EVGA GeForce GTX 980 Ti 6GB Classified (x2)
  • Corsair HX1200i 1200W PSU
  • Samsung 256GB SSD (Running Windows 10)


But the problem is, the one GTX 980 Ti is NOT being recognized in the bottom red PCi slot (with or without SLI).
Both cards work individually when placed in the top slot, and the bottom slot CAN recognize a spare GTX 660 I had, but the BIOS, the Device Manager and the Nvidia Control Panel fail to acknowledge the bottom 980 Ti is there. There's no error message, it just doesn't show anything.
Windows 10 is completely up to date.

Below is a list of troubleshooting steps I took


  • Updated BIOS
  • Cleared CMOS
  • Tested each graphics card in Slot 1
  • Tested each graphics card in Slot 1 with a GTX 660 in Slot 2 (recognized)
  • Tested each graphics card in Slot 1 and 2
  • with and without SLI bridge attached


In addition I bought a 1200W power supply to make sure it wasn't any of the cords or a lack of power problem, cycled through a myriad of settings through the BIOS that I don't even remember. It seems I've tried everything under the sun to get that bottom PCi slot to recognize the 980 Ti, but it just can't.

This is a longshot, and I know this is a very specific problem, but if there's any help anyone can offer, I would be greatly appreciative..

Thank you for your time.
773 Views
11 REPLIES 11

Nate152
Moderator
Hello eranostal

Welcome to the ROG forum.

That is a strange problem you're facing, both 980 Ti's work in the first pcie slot and a gtx 660 works in the second red pcie slot.

This would make me want to look over the psu and pcie power cables.

This is actually the second PSU I tried to see if it's working.. haha.

I'm not an expert at figuring out hardware (certainly not after this affair).. the cords seem fine, and I'm not sure if being in the second slot requires a higher demand of power?
Both cards are being powered the same way (I apologized if my wording is off), both cards are being powered via an 8 pin to 2 6+2 pin PCi Xxpress power cables. Is that not enough for the bottom card?

Nate152
Moderator
Two 8 pin pcie power cables is what the evga 980 Ti classified calls for and it seems you got it right.

Double check the psu end to make sure they are completely secured.

Two 6+2 pin pcie power cables for each 980 Ti.

They seem to be fairly sound in there, and just to specify again that it is one 8-pin to two 6+2 pin connectors.

I swapped the connectors as well from card to card.. same problem, top card still works, bottom one no luck.

Nate152
Moderator
I'm not quite understanding one 8 pin to two 6+2 pin connectors.

The 980 Ti classified has two 8-pin pcie power connectors, you would use two 6+2 pin pcie power cables for each 980 Ti.

Argh, sorry, like I said I'm not the most knowledgeable when it comes to this stuff.

It's an 8-pin connector when it plugs into the PSU, but the end of the cord branches off into two sets of 6+2 connectors.

This works no problem for the top card, maybe the bottom card isn't getting enough juice? No idea..

Nate152
Moderator
OK so you have 4 pcie power cables with an 8-pin that connects to the psu with two 6+2 pin connectors on the other end for a total of 8 6+2 pin pcie power cables, Gotcha !

I'm not sure why it's not working and it seems to be some sort of power issue as you suggest.

Try another pcie cable on the second 980 Ti, use the same cables from the same psu.

I just tried swapping the cords, same problem.

I also tried using cords from the previous PSU I had, still nothing...

It is worth noting that the card does turn on, and the fans spin and the card gets warm.

Since an older card does work on the bottom slot.. I was on the path that it's maybe more of a problem with the board not recognizing the card.. but why only the bottom slot?
Even if there's no card in the top slot, the bottom slot still refuses to recognize the bottom card.

Nate152
Moderator
Don't use cables from another psu, make sure ALL the cables you're using are from the Corsair HX1200i.

Well I'm not sure what to do next it sounds like it's working but not recognized and I find this strange that a gtx 660 works in the 2nd pcie slot.

You could try clearing the cmos and updating the bios then if this doesn't help I'll suggest to contact evga to see if they have any suggestions.

Toll Free: 1-888-881-3842

Let me know what they have to say if clearing the cmos or updating the bios doesn't help you.