The VIVO output on graphics cards is often not used by those who have no need to connect their computer to a TV. Also, there can be issues in software supporting the use of VIVO ports.
A computer using VIVO must have software that can handle an input signal. For example, in the case of Nvidia GeForce series 6 and 7 video card users this means downloading Nvidia's WDM drivers.
Additionally, On Windows XP computers that use GeForce video cards with Scalable Link Interface (SLI) mode enabled, using a TV to display part of the desktop via VIVO is disabled, just as dual-monitor mode is disabled. Confusingly, however, some distorted images may be visible on a properly-connected VIVO-driven television display at boot-up due to the fact that prior to the OS loading the display driver, the video bios might initialize outputs that are then unavailable once the OS takes over and the driver loads into SLI mode.