G'day fellas,
 
(Sorry if this is a long post! Just trying to eliminate all most factors. If I'm wrong, bare with me i'm not the most knowledgable person on this!)
Now I know this thread has been replicated many times over, but I just really have nowhere to turn and am completely stumped and would like to get my hardware specific info.
Before I start, here are my specs:
 
 

• CPU: Intel® Core™ i7 4790K
• CPU Cooler: Corsair Hydro Series H100i CPU Cooler
• Motherboard: Gigabyte GA-Z97X-SOC
• Graphics: 2x EVGA GeForce GTX 780 Ti 3GB Superclocked
• Memory: 2x G.Skill Ares F3-1600C9D-8GAO 8GB (2x4GB) DDR3
• Solid State Drive: Samsung 840 EVO Series 250GB SSD
• Hard Drive: Seagate Barracuda 2TB ST2000DM001
• Case: NZXT H440 Mid Tower Case Black/Orange
• Power Supply: SilverStone Strider Plus 1000W ST1000-P Modular PSU
• Operating System: Microsoft Windows 8.1 64bit OEM

 
Okay, so I got 2 EVGA 780 Ti's brand new yesterday, along with a brand new EVGA 3-way SLI bridge (and BOY they look good).
But, as is typical with me, the installation wasn't as smooth as I'd liked it to be. The SLI notification bubble will just not show up. Of course, it recognises both cards, but will not give me the enable SLI notification/option. Here's the things I've tried already:
 

• Reseating both cards
• Swapping the card order
• Completely re-installing drivers with Driver Sweeper (with both cards in)
• Turning the SLI bridge the other way around :pt1cable:
• Booting with one card, installing drivers, shutdown then install second card.
• Motherboard BIOS is also the latest version (not sure about the cards though, I'm not too good with that stuff and don't want to break anything).

 
Now, the funny thing is I previously had 2 Galaxy 780 Ti Hall of Fame Editions running in SLI a couple days ago (they ran fine), but the cards were way too big so I swapped them for the EVGAs. But the EVGAs just refuse to work! I have thoughts on what possibly could be the problem, which I'll include photos just below.
Maybe it's the Network card I have in the middle PCIe slot? I was also thinking the power cables (brand new), because the Hall of Fame's ran with 16 power slots compared to EVGAs 14 power slots:
 

 
These are my power cables. I have the 16 pins there - notice due to the decrease in power slots, I have a two pin connector not plugged in anymore. The others go in fine:
 

 
And lastly, I have a PCIe network card (not a cheap one) plugged in to a slot in between my cards. At the top right you can also see what I mean about have a two-pin connector unplugged doing nothing due to the the amount of slots:
 

 
Would any of this have something to do with it? I feel like I've tried the driver solution a million times and nothing :(
Also, the EVGA light on the SLI bridge lights up when plugged in too! It just won't give me SLI!
 
Any info would be greatly appreciated.

bob16314
Take your network card out of PCIEX4_1, it's causing PCIEX8 (where your bottom graphics card is) to run in x4 mode..SLI needs slots to run in x8 mode at least..Refer to your for details.

Thanks for your fast reply! I see, so could I put my network card in the very bottom PCIe slot and that would stop interference?
 
Cheers!

Great, thanks heaps for the info. This is the first PC I've built - still learning most of this stuff.

So ideally both cards would wanna run on a 16x slot for the best SLI performance? And you can tweak your mobo to do that and/or buy ones that physically have more than one 16x slot?