SLI 2x Asus GeForce 7800 GTX Extreme
Owners of single-card packages of the GT and GTX are faced with a problem when planning to upgrade to SLI mode, as neither board comes with an SLI bridge card, which is needed to connect two identical NVIDIA cards to use them in SLI mode.
SLI Bridge for Connecting Two Graphics Cards
Once the cards are connected, the graphics driver needs to be set to SLI operation. Asus' Smartdoctor utility is smart indeed, recognizing the second board immediately. Again, the overclocking utility foregoes any warning about the loss of warranty when overclocking, and would allow setting both cards to run at up to 510/1400 MHz (GPU/memory). In single-card mode, this setting proved much too high, resulting in visual artifacts in 3DMark.