No SLI option on Nvidia Control Panel?

[Loupeitak]

Hey there, first post and pretty much a PC newbie, but enthusiast!

 

So I just finished my first fully DIY PC build after saving up for a couple of years. I went with 2 EVGA GTX 780 Ti SC hoping to run them in SLI mode. My motherboard is the Asus X79-Deluxe and I've got everything plugged into an RM 1000, which should be plenty.

 

Everything went smoothly and I got pretty much everything down. However, after installing the latest Nvidia drivers, I tried to turn on SLI mode in the Nvidia Control Panel, but the option was not there. I checked the SLI Bridge, making sure it was connected properly and I tried another bridge hoping that was the problem. I also tried connecting the bridge to both the connections on the GPUs (left and right side), but the option still doesn't show up. What am I doing wrong? What could be the issue? Any help would be greatly appreciated!

 

Thank you in advance and best regards to everyone!

 

EDIT - I forgot to mention, both GPUs are recognized in the device manager, but running without SLI, one of them is pretty much idling at much lower temperatures. I am also on Windows 8.1 if it makes any difference.

[AlwaysFSX]

Try reinstalling the driver again, make sure you download the 8.1 version and double check whether you're using 32 or 64 bit.

[mooseducks86]

 

EDIT - I forgot to mention, both GPUs are recognized in the device manager, but running without SLI, one of them is pretty much idling at much lower temperatures. I am also on Windows 8.1 if it makes any difference.

I had this problem when I installed mine. I couldn't read the writing on the PCB, so I referred to the manual, that listed the slots incorrectly (or I misunderstood)

I had the one GPU in the 16x slot, and the other in a 4x slot instead of the 16/8x slot.

 

One of the trouble shooting suggestions I got from EVGA (before I realised my goof) was uninstalling the cards in device manager, shut down, switch the cards around, and reinstall. The SLI option now only shows up in nvidia control panel when you have SLI compatible cards. You only need to use the first bridge connecter (left hand side) and try flipping the bridge around.

 

Are the cards identical revisions? Does your motherboard require an extra PCIe power connector to support SLI? Mine was right near the 16x slot.

[isteelsolz]

yeah, nvidia only allows SLI in slots with a minimum bandwidth fo 8x. Check in the maunual to see which slots are the 8x slots and then re position the card

[dragoon20005]

Under your mobo BIOS under Advanced Menu

 

look for System Agent Configuration

 

make sure all PCI-E lanes are set to Gen 3 mode

 

 

 

swap the position of the GPUs

 

Use ONLY Slot 1 and 3 for SLi mode

 

 

I just read your mobo manual

[Loupeitak]

I had the 2nd GPU on the 3rd PCI slot. Moved it to the 4th slot and SLI is now enabled. My mistake there . Thanks to everyone who helped!