System Board Problems; Video And Monitor Problems - Dell OptiPlex SX270 User Manual

Check for interrupt request conflicts —
No sound from headphones
Check the headphone cable connection —
Adjust the Windows volume control —
is turned up and that the sound is not muted.

System Board Problems

Fill out the Diagnostics Checklist as you complete the following checks.
Perform all checks in "Keyboard
CAUTION: Before you begin any of the procedures in this section, follow the steps in
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,
CAUTION: Before you begin any of the procedures in this section, follow the steps in
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,

Video and Monitor Problems

Fill out the Diagnostics Checklist as you complete these checks.
If the screen is blank
NOTE: See the monitor documentation for troubleshooting procedures.
Check the monitor 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 —
missing pins.)
Check the RGB/DVI video input switch found on some Digital Flat Panel displays —
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) —
defective.
Test another monitor — If another monitor is available, connect it to the computer.
Check the diagnostic lights — See
Run the Dell Diagnostics — If any tests fail,
If the screen is difficult to read
See "Resolving Software and Hardware
Ensure that the headphone cable is securely inserted into the headphone connector.
Click or double-click the speaker icon in the lower-right corner of your screen. Ensure that the volume
Problems"
contact Dell.
If the power light is off, firmly press the button to ensure that the monitor is turned on. If the power light
Check the connector for bent or broken pins. (It is normal for monitor cable connectors to have
If you are using a video extension cable and removing the cable solves the problem, the cable is
"Diagnostic Lights."
contact Dell.
Incompatibilities."
"CAUTION: Safety Instructions."
"CAUTION: Safety Instructions."
Check that the desired video input is selected.
contact Dell.