Dell OptiPlex SX270N - Manual (Page 94)

No sound from headphones
System Board Problems
Fill out the Diagnostics Checklist as you complete the following checks.
Video and Monitor Problems
Fill out the Diagnostics Checklist as you complete these checks.
If the screen is blank
If the screen is difficult to read
Check for interrupt request conflicts — See " Resolving Software and Hardware Incompatibilities ."
Check the headphone cable connection — Ensure that the headphone cable is securely inserted into the headphone connector.
Adjust the Windows volume control — Click or double-click the speaker icon in the lower-right corner of your screen. Ensure that the volume
is turned up and that the sound is not muted.
Perform all checks in " Keyboard Problems "
CAUTION: Before you begin any of the procedures in this section, follow the steps in " CAUTION: Safety Instructions ."
Reinstall the battery —
1. Turn off the computer and devices, disconnect them from their electrical outlets, wait 10 to 20 seconds, and then open the computer
cover.
2. Remove the battery, wait 5 minutes, and then reinstall the battery.
3. Close the computer cover, reconnect the computer and devices to electrical outlets, and then turn them on.
If the problem still exists, contact Dell .
CAUTION: Before you begin any of the procedures in this section, follow the steps in " CAUTION: Safety Instructions ."
Replace the Memory Modules —
1. Turn off the computer and devices, disconnect them from their electrical outlets, wait 10 to 20 seconds, and then open the computer
cover.
2. Rotate the power supply away from the system board.
3. Replace the memory module(s).
4. Close the computer cover, reconnect the computer and devices to electrical outlets, and then turn them on.
5. If the RAM count displayed does not correctly match the actual amount of memory installed in the computer, contact Dell .
NOTE: See the monitor documentation for troubleshooting procedures.
Check the monitor power light — If the power light is off, firmly press the button to ensure that the monitor is turned on. If the power light
is lit or blinking, the monitor has power. If the power light is blinking, press a key on the keyboard or move the mouse.
Check the monitor cable connection — Check the connector for bent or broken pins. (It is normal for monitor cable connectors to have
missing pins.)
Check the RGB/DVI video input switch found on some Digital Flat Panel displays — Check that the desired video input is selected.
Test the electrical outlet — Ensure that the electrical outlet is working by testing it with another device, such as a lamp.
Swap the power cables — Swap the computer and monitor power cables to determine if the power cable is defective.
Test the video extension cable (if used) — If you are using a video extension cable and removing the cable solves the problem, the cable is
defective.
Test another monitor — If another monitor is available, connect it to the computer.
Check the diagnostic lights — See " Diagnostic Lights ."
Run the Dell Diagnostics — If any tests fail, contact Dell .