On the Power Macintosh 8500, the video out circuitry detects the presence of a television and the Mac OS determines the choices available for television output in the control panel. If a television is available, the Mac OS allocates some Video RAM (VRAM) for the TV output device and either mirrors the computer's main display or uses the television as a second monitor.
If the television or other video output device is not attached, but the TV option is available in Sound and Displays control panel, you need to open the unit to check the cable connection.
WARNING:
These directions are provided primarily for Apple Service providers. If you attempt to perform upgrades or repairs yourself, any damage you may cause to your equipment will NOT be covered by your warranty.
IMPORTANT:
Your computer contains electrically sensitive parts. To avoid damaging your computer, discharge static electricity that may be on your clothes or body by touching the power supply case before working with the assembly.
Examine the internal AV ribbon cable and make sure it is attached between the logic board and the external RCA video/sound connectors on the back panel of the computer. The internal ribbon connector must be attached to the logic board for the detection circuitry to operate properly. If the cable is not connected properly to the logic board, the computer assumes a television is available. If the cable is not connected properly, reconnect the internal cable to correct this problem.
Article Change History:
28 Aug 1995 - Added Warning information and clarified the disscussion.
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