There are two versions of the GeForce GTX 295 card. One card version has two DVI and one HDMI connectors, the other version has two DVI connectors. The card with DVI and one HDMI does work in 3D Vision Surround but only with 3D projectors. It does not work with 3D Vision-Ready LCDs since they require three dual-link DVI connectors on the GPU, which are only available when you are running SLI (two cards).
You can also pair two GeForce GTX 295 cards in Quad SLI mode and work with 3D Vision Surround mode in a future driver update. However, please note that in the first Beta driver for 3D Vision Surround, we do not recommend running GeForce GTX 295 Quad SLI because there are bugs in the driver which may result in system instability. We will be providing a future driver update to support this configuration.