Maximus V Formula SLi Unstable PLEASE HELP

[ExGreyFox]

I just can't seem to put my finger on this one. Thus far I have been running a single Gigabyte GTX 780 Ti GHz with 3 monitor surround and performance has been rock solid and stable. Just got my second Gigabyte GTX 780 Ti GHz a few days ago for an SLi setup with my 3 monitor surround and have been plagued with instability.

My system specs:

Intel i7-3770k Ivy Bridge@4.6GHz 1.35v
Maximus V FORMULA BIOS 1903
GIGABYTE SLi GTX 780 Ti GHz WindForce x3
G.Skill Ripjaws 8GB DDR3 1600
Thermalright Venemous-X RT
OCZ Vertex 4 128GB SATAIII SSD (OS)
Crucial M4 128GB SATAIII SSD
Hitachi 500GB 7200rpm
Case HAF 932
Corsair Ax1200i 1200 watt PSU


When I say instability, it involves the following: game freezes, sound keeps playing, screens go black and sound continues to play. And nothing can get me out of this without resetting the PC. On a few occasions I've been able to ctrl alt del into desktop where my mouse bogs down to 1 FPS movement and then i hard freeze and have to reset. My games also look like they bog down to about 1 or 2 FPS right before the crash and then it hard freezes and my monitor starts flashing on and off with a black screen. The crash can happen from anywhere to 15 min into gaming to all the way to about 3 hours.

Here are the things I have tried so far:

1. A clean re-install of windows
2. Several older driver versions
3. tested one GPU at a time, both work solid with no issues
4. Down clocked the GPU core on both GPUs back to 1085 (since the gtx 780 Ti's come with a boost of 1150)
5. Tried a different SLi bridge cable
6. Updated my Maximus V Formula BIOS to latest version 1903
7. Went down to SLi on a single monitor with surround disabled.

After all of this the same problem still persists.

Any help is greatly appreciated.

UPDATE: This is what I see in my even viewer every time I crash:

Warning: Display driver nvlddmkm stopped responding and has successfully recovered.

Error: The description for Event ID 14 from source nvlddmkm cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

\Device\Video7
1593(2960) 00000000 00000000

[PowerOver9K]

You have your 2nd 780 in the correct slot? What slot are you in?

[ExGreyFox]

PowerOver9K wrote:
You have your 2nd 780 in the correct slot? What slot are you in?

Yes, cards are in the 1st and 2nd slot. This is what I see in my even viewer everytime I crash:

Warning: Display driver nvlddmkm stopped responding and has successfully recovered.

Error: The description for Event ID 14 from source nvlddmkm cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

\Device\Video7
1593(2960) 00000000 00000000