Heres what i found...try this...done with GTX 460 sli
 

 
Oddly there is still no 3DMark11 profile in latest versions of NVIDIA drivers (like in the very last R266.35). And manual SLI tweaking in NVIDIA Control Panel changes nothing. So how to enable SLI with 3DMark11?

Simply by using a tiny tool developped by NVIDIA and called GeForce 3D Settings Profile Manager. You can download it here: Manage your SLI Profiles with NVIDIA GeForce SLI Profile Tool.

1 – Start Geforce_SLI_Profile_Tool.exe

2 – Export the profiles file
 

 
 
3 – Add this block in the profiles file:
Profile "3DMark11"
   ShowOn GeForce
   ProfileType Application
   Executable "3dmark11.exe"
   Executable "3dmark11cmd.exe"
   Executable "3dmark11demo.exe"
   Executable "3dmark11workload1.exe"
   Executable "3dmark11workload2.exe"
   Setting ID_0x00a06946 = 0x084000f5
   Setting ID_0x1033cec1 = 0x00000003
   Setting ID_0x1033cec2 = 0x00000002
   Setting ID_0x1033dcd2 = 0x00000004
   Setting ID_0x1033dcd3 = 0x00000004
   Setting ID_0x1095def8 = 0x02c00005
   Setting ID_0x209746c1 = 0x04280001
   Setting ID_0x20ebd7b8 = 0x00000020
 EndProfile





4 – Import the profiles file



5 – Enable the SLI Visual Indicator (NVIDIA Control Panel / 3D Settings)
6 – Start 3DMark11.



And here are the scores:
GTX 460 SLI:
- X1596
- P4992
- E8072
GTX 460 single GPU:
- X947
- P3251
- E5270


Source: Geeks3d

Download Sli Profile tool : SLI Profile Tool

Good find I will try this out.

ERROR:
There was a problem importing the settings from disk.
 
Doesn't work for me

I hate to be a party pooper but JacobF already posted...
 
This is a temporary fix for SLI in 3DMark 11, this will give you improved performance in SLI, however, there is some flickering while the test is running.
 
Benchmark:
Without Update: P4,759
With Update: P7,600
 
Version 38 Beta - Based on NVIDIA 266.35 BETA Driver
Changelist:

New profiles from EVGA SLI Enhancement Patch:

    * Enables temporary SLI support in 3DMark 11

http://cdn.evga.com/sli/SLI_Enhancement_38_Beta.zip
 
True SLI support (without flickering) will come from NVIDIA soon, this is only a temporary fix.
 
 
http://forums.evga.com/tm.aspx?m=774133