Asus P5NSLI - Manual (Page 119)

ASUS P5NSLI Series 3-17
8. Click the Enable SLI multi-GPU check box.
9. Click OK when done.
Setting the ASUS AI Selector utility
From the AI Selector utility, select Dual Video Cards then click Yes to
restart your system. Refer to Table 1 below for the AI Selector card
settings.
Table 1 AI Selector settings
AI Selector setting PCIEX16_1 (blue) slot PCIEX16_2 (black) slot
Card Type Speed Card Type Speed
Single Video Card Qualified PCIe x16 x16 - -
graphics card
SLI mode Qualified SLI-ready x8 Qualified SLI-ready x8
Dual Video graphics cards graphics card
Card Multi-monitor, Qualified PCIe x16 x8 Qualified PCIe x8, x4,
RAID or LAN graphics card graphics card, x2, x1
setup RAID or LAN card
When the SLI mode is disabled, the multi-monitor mode is automatically
enabled. Use the NVIDIA nView utility to configure your multi-monitor
setup.