Power Macintosh Update for AV-Equipped Computers. On certain AV-equipped Power Macintosh computers the card that controls the audio-visual functions may not be set up correctly, causing Macintosh 21" monitors to be unviewable. This extension will fix the problem. The extension is included in the floppy disk named 'Power Macintosh AV Update Disk' You may have obtained the extension from an online service such as AppleLink. This extension was known as TYC in early version.
