My friend has 1 PCIe video card, and an SLI (which we hope just means 2 regular 16x PCIe slots with no strings attached) motherboard. He needs some extra displays, and was thinking of getting another ...
"High performance" power mode = SLI. Unfortunately the default power setting is "balanced". That mode runs one video card until it detects an app requesting 3D graphics and then it switches to SLI.