The B004-DUA4-HR-K is a 4-Port DVI/USB KVM Switch with audio and USB 2.0 peripheral sharing. It allows you to access, control, boot and reboot four computers from a single USB keyboard, USB mouse, and monitor. Switching between connected computers is quick and simple using keyboard hotkeys or pushbuttons. An independent audio/mic and USB peripheral switching function allows for an uninterrupted experience. A computer can be printing on a printer connected to one of the USB 2.0 peripheral ports, while you listen to audio from and access another computer; all at the same time.The B004-DUA2-HR-K uses DVI-I technology, allowing for the transmission of a digital (up to 1920 x 1200) or analog (up to 2048 x 1536) signal. A DVI to VGA adapter, such as Tripp Lite's P126-000, is required for conversion to an analog monitor. Whichever you use, full time DDC support provides the necessary EDID information required for optimal video performance on Windows 7 and other operating systems. Compatible with all major operating systems.