You can run SLI on this board...
I'm using 2x 285 GTX in SLI and it work perfectly, simply do the following:
"Install 2 identical Cards with SLI support "or 2 with the same GPU" then:
1- Uninstall and remove all sli mods and patches "Do not restart"
2- Uninstall and remove intel's Chipset driver "Do not restart"
3- Get "Diver Sweeper" and install it - here is a link:
Driver Sweeper 2.5.0
4- Using Driver Sweeper, check and clean every thing named Nvidia "Drivers, Physix...etc"
5- When done, make a restart then install the latest Chipset Driver from intel
6- Download SLI_Patch 1.2 beta from here:
SLI-Patch-1.2b
7- Disable UAC - Control Panel -> User Accounts & Family Safety -> User Accounts -> Change User Accounts Control settings -> Move the slider down to the bottom and click Ok
8- With UAC Disabled run SLI Patch 1.2 and click install
9- Restart now and you should see a boot menu with 2 options ( Windows 7 & Windows 7/......SLIPatch X64 ) choose the patched one
10- Install Nvidia Drivers version 260.xx "i'm using 260.99 32bit Xtreme tweaked" you can find those tweaked drivers at
www.tweakforce.com
11- After installing the drivers go to Nvidia Control Panel then under 3D Settings click Set SLI and Physix
12- Under SLI Configuration, choose Maximize 3D Performance and click Apply
13- To see SLI usage indicator in your games click 3D Settings menu from the top of Nvidia Control Panel and check "Show SLI Visual indicator
Tested with the following :
Q6600 G0 @ 3.6 + Asus Rampage Extreme X48 1301 Bios + 2x 2GB RipJaws-X CL6 1600MHz + 2x GTX 285 1GB + SLI_Patch 1.2beta + Xtreme-G 260.99 Drivers + Windows 7 Ultimate SP1 32bit
*Note that if you're using non identical cards but uses the same GPU "uses different speeds like me" nVidia Controls won't adjust the speeds to the slower card like it should be! get EVGA Precision and adjust them manually so both cards run at the same speed "clock down the speeds of the faster card to the speeds of the lower card" and save the profile and make it run on windows startup..
*Another Note I've noticed with this board, if you're booting with BIOS1 and made a BIOS update, you should copy BIOS1 to BIOS2 to update the second chip or you'll be restored to the old BIOS 0301 on the second chip if BIOS1 fails, thus will make BIOS1 unbootable until you copy the old version in BIOS2 to BIOS1 and loose your update !!