A DVR card can only be installed in a Windows pc. The card requires a vacant PCI slot on the motherboard for installation. A PCI Express or AGP slot will not work. It must be PCI. It must be Windows computer. The best and faster video that can be displayed or viewing is 30 frames per second (FPS) per camera. 30FPS per camera is considered Real Time. In other words a "120 FPS 4 camera" card is considered a real time card. On the other hand a "30FPS 4 camera" card is not real time. Then each camera is only allocated approx. 7FPS per camera and then playback and live viewing will be jerky and not fluid.