The MD MPEG-4 Video Card driver refers to a driver for a video card or graphics card that is capable of decoding or processing MPEG-4 video. MPEG-4 is a widely used video compression standard, and such cards are typically used for hardware-accelerated video decoding, which improves video playback performance and quality.
However, "MD MPEG-4" doesn't point to a specific, widely-known brand or model of a video card, so the term could refer to different hardware solutions from different manufacturers that are designed to handle MPEG-4 video.
To answer your question comprehensively: