HP DC7800 - Manual (Page 256)

Power LED flashes Red five times, once every second, followed by a two second pause, and the computer beeps five
times. (Beeps stop after fifth iteration but LEDs continue flashing.)
Cause Solution
Memory is installed incorrectly or is bad. 1. Reseat DIMMs. Power on the system.
2. Replace DIMMs one at a time to isolate the faulty module.
3. Replace third-party memory with HP memory.
4. Replace the system board.
Solving Processor Problems
If you encounter processor problems, common causes and solutions are listed in the following table.
Table D-14 Solving Processor Problems
Poor performance is experienced.
Cause Solution
Processor is hot. 1. Make sure the airflow to the computer is not blocked.
2. Make sure the fans are connected and working properly
(some fans only operate when needed).
3. Make sure the processor heatsink is installed properly.
Power LED flashes Red three times, once every second, followed by a two second pause.
Cause Solution
Processor is not seated properly or not installed. 1. Check to see that the processor is present.
2. Reseat the processor.
Power LED flashes Red eleven times, once every second, followed by a two second pause.
Cause Solution
The current processor does not support a feature previously
enabled on this system. 1. Install a TXT capable processor.
2. Disable TXT in the Computer Setup (F10) utility.
3. Reinstall the original processor.
Solving CD-ROM and DVD Problems
If you encounter CD-ROM or DVD problems, see the common causes and solutions listed in the
following table or to the documentation that came with the optional device.
Table D-13 Solving Memory Problems (continued)
244 Appendix D Troubleshooting Without Diagnostics