Hello everyone, I have an issue with my system that I hope someone here can help resolve.  I recently picked up a second GTX 980; I have been running a single 980 for the past year.  Whenever I connect both cards, the computer posts, the Windows logo appears for a flash, then the system restarts.  On the ensuing load attempts, the Windows logo appears with the text "Running auto repair", then cycles.  If I remove the second card, the Auto Repair reports that the machine "failed to shutdown gracefully," likely from the initial restart.
 
Things I have tried so far:

• Installed each card by itself (successful load into W10)
• Installed each card by itself in different PCIx16 slots (successful load)
• Verified that the new card (a FTW) has the proper 6 and 6+2 pin power cables
• Reset mobo OC to factory settings
• Tried the SLI setup both with and without the SLI bridge (failed)

A year ago, this rig was running SLI GTX 480s, so I can't imagine there is a lack of juice to run two 980s.  From what I read, two 980s have about the same power draw as one 480.
 
Does anybody have ideas for me to try?  I haven't been able to call EVGA Customer Service yet, but I will likely try that later when I get home.
 
Update 12/5:

I am able to load into the OS and my system runs!  I updated my mobo BIOS to the latest version, as well as applied the "Memory Low Gap" fix mentioned by Sajin.  After some experimenting, it was definitely the Memory Low Gap fix that resolved this.  Thank you for finding that Sajin!!!
 
I have now, however, encountered another issue.  My system loads at default settings, but the moment I go to overclock my CPU (back up to 4ghz, but also tried 3.8ghz), the same behavior occurs as if I didn't apply the Memory Low Gap fix.  Does anybody know the effect setting MLG to 3G and overclocking the CPU have?  I would like to increase the cpu clock speeds so I can take better advantage of my new SLI setup.

And does your mobo have the latest bios update?
 
http://www.evga.com/support/download/
 
There is also some Win 10 drivers available there as well, ie. Chipset Driver.

The thing which is odd is that the PC doesnt even run without the SLI bridge. Just about every scenario previously deals with the PC booting without the bridge, but not with the bridge.

The fact that it doesn't boot with either says a lot though.
It means:
1) It's not the SLI bridge
2) It's not the SLI plugs

Also the cards work on their own so they're probably not faulty.

From this, I think it's probably the motherboard or software (Win10). The board worked with a 480SLI so it's not the PCI lanes/slots, but it could be the BIOS. You could also try reinstalling Win10, but that's a commitment maybe you're not interested in, but it would be a good thing to try before RMA. Also try reinstalling the drivers using DDU, it's crashing near the time the driver loads and it may be crashing due to an issue (corrupt file or something).

Thank you all for your suggestions so far!
 
PSU: Corsair 1000HX
 
I have not updated my mobo BIOS yet, I will try that when I get home from work.  I will try booting into safe mode.

You could also try this... http://www.evga.com/suppo...mmain.aspx?faqid=59549

Update to my issue:
 
I am able to load into the OS and my system runs!  I updated my mobo BIOS to the latest version, as well as applied the "Memory Low Gap" fix mentioned by Sajin.  After some experimenting, it was definitely the Memory Low Gap fix that resolved this.  Thank you for finding that Sajin!!!
 
I have now, however, encountered another issue.  My system loads at default settings, but the moment I go to overclock my CPU (back up to 4ghz, but also tried 3.8ghz), the same behavior occurs as if I didn't apply the Memory Low Gap fix.  Does anybody know the effect setting MLG to 3G and overclocking the CPU have?  I would like to increase the cpu clock speeds so I can take better advantage of my new SLI setup.
 
Thanks again!

maniacvvv
Are you showing all 6gigs available in Windows? (prior to the OC) yes
 
What RAM voltage and timings are you using? 1.65v
What is the "memory target frequency" showing in BIOS with your OC settings before attempting to boot? 1594mhz
*(remember that the X58 does not use XMP correctly and is known to overvolt and set incorrect timings, so XMP MUST be turned off and it must be done manually in BIOS)  
 
How much extra VTT are you using? Set to auto
 
I have had 3 different sets of SLI'd cards in my X58, and all of them required some tweaking from previous stable overclocks, mostly centered on RAM