HP Compaq d330 DT Troubleshooting Manual page 25

Solving Power Supply Problems (Continued)
Problem
Power LED flashes Red,
once every two seconds.
OR
Power LED flashes Red four
times, once every second,
followed by a two second
pause.
Troubleshooting Guide
Cause
Power failure (power
supply is overloaded).
www.hp.com
Troubleshooting Without Diagnostics
Solution
1. Check that the voltage selector,
located on the rear of the power
supply, is set to the appropriate
voltage. Proper voltage setting
depends on your region.
2. Open the hood and ensure the
4-wire power supply cable is
seated into the connector on the
system board.
3. Check if a device is causing the
problem by removing ALL
attached devices (such as hard,
diskette, or optical drives, and
expansion cards). Power on the
system. If the system enters the
POST, then power off and
replace one device at a time
and repeat this procedure until
failure occurs. Replace the
device that is causing the
failure. Continue adding
devices one at a time to ensure
all devices are functioning
properly.
4. Contact an authorized service
provider to replace the power
supply.
5. Replace the system board.
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