Symptom
A monitor with an Apple Display Connector displays no video when connected to a Power Mac G4 Cube computer. However, if you connect a monitor with a VGA-style connector video appears on the display.
Solution
This article covers repair procedures for Apple Authorized Service Providers on selected Apple products, but the procedures are being published in the Knowledge Base for the general public for educational purposes only. At this time, there are a limited number of repairs that a customer can perform and these are covered under the Customer-Installable Parts program. For information on this program please visit http://www.info.apple.com/installparts/ .
If you have not been authorized to perform these procedures, please contact Apple (800-APL-CARE in the U.S.) or your local Apple Authorized Service Provider to schedule a repair.
Follow these steps:
1. Connect a known-good monitor with an Apple Display Connector (ADC).
2. Verify the monitor with an ADC has a known-good power source.
3. Make sure the display cable from the monitor is securely connected to the video card.
4. Make sure the video riser card and the video card are properly seated in their connectors.
5. Verify the cable connector at J3 on the video riser card is pushed in all the way. This connector provides the voltage for the ADC.
Figure 1 Cable connector at J3
6. If the monitor with an ADC still displays no video, contact Apple Support for further assistance.