Settings:
1920x1080 (FullScreen) @ Max Detail Settings
Note: fps cap @ 60fps
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Before: GPU1= 98%; GPU2= 1%
After: GPU1= 56%; GPU2= 56% (fps cap)
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=> SLI compatibility bits: "0x03402005 (CS: Global Offensive, Firefall, Dishonered,...)"[/b]

0. Download [www.nvidia.com] & install the latest NVIDIA Driver
1. Add "lotdgame.exe" to your NVIDIA 3D Profile Settings
2. Download [www.guru3d.com] & open NVIDIA Inspector (note: also extract "CustomSettingNames_en-EN.xml")
2.1 Go to “Driver Profile Settings” --> Set Global Driver Profile to "lotdgame.exe"
2.2 Then set "SLI compatibility bits" to 0x03402005 (CS:Global Offensive,Firefall,Dishonered...)
2.3 & set all other settings as shown below... --> Apply changes
3. Enjoy Deadlight with SLI enabled

If you have "too many" fps left, you can try tweaking the Nvidia Graphics Settings like this...
(note: I'm forcing only 2x MSAA, as the resolution of 3840x2160 caused a CTD with 4x enabled when launching the game. The resolutions of 2880x1620 & 1920x1080 work fine with 4x MSAA, or more...)

I5 2500K @4500MHz
GTX 460 SLI @840MHz / 2000MHz
16GB DDR3 @1600MHz
120GB SSD
Win 8.1 Pro 64bit

Tested on the following NVIDIA Drivers:

• 326.41 BETA
  
• 326.80 BETA
  
• ...
  
• 337.88 WHQL

Unfortunately after installing a new Nvidia Driver, you have to set your SLI Profile again!
Even with the "Express Installation"... :(
(But only the SLI Profile Settings, the tweaked Settings stay the same.)
--> You can "prevent" that by Exporting all customized profiles (with Nvidia Inspector) and import them back after the Nvidia Driver Installation!
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PLZ Rate if you like... :)

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