Table 7. Beep errors (continued)
One long and two short beeps
The video function has a problem. Have the computer
serviced.
Five beeps The system board has a problem. Have the computer
serviced.
Memory module problems
Print these instructions now and keep it with your computer for reference later.
If your memory module is not operating properly, check the following items:
1. Verify that the memory module is installed and seated correctly in your computer.
It might be necessary to remove all added memory modules to test the computer with only the
factory-installed memory modules, and then reinstall the memory module one at a time to ensure
a proper connection.
2. Check for error messages during startup.
Follow the appropriate corrective actions for power-on self-test (POST) error messages.
3. Verify that the latest UEFI BIOS for your model has been installed.
4. Verify the proper memory conguration and compatibility including the maximum memory size and the
memory speed.
5. Run diagnostic programs. See “Diagnosing problems” on page 125.
Networking problems
The following are the most common networking problems:
Ethernet problems
• Problem: Your computer cannot connect to the network.
Solution: Make sure that:
– The cable is installed correctly.
The network cable must be securely connected both to the Ethernet connector of your computer and
to the RJ45 connector of the hub. The maximum allowable distance from the computer to hub is
100 meters. If the cable is connected and the distance is within acceptable limits but the problem
persists, try a different cable.
– You are using the correct device driver.
1. Go to Control Panel and click Hardware and Sound ➙ Device Manager. If you are prompted for
an administrator password or conrmation, type the password or provide conrmation.
2. If the exclamation mark ! is displayed next to the adapter name under Network adapters, you
might not be using the correct driver or the driver might have been disabled. To update the driver,
right-click the highlighted adapter.
3. Click Update Driver Software, and then follow the instructions on the screen.
– The switch port and the adapter have the same duplex setting.
If you congured the adapter for full duplex, make sure that the switch port also is congured for
full duplex. Setting the wrong duplex mode can degrade performance, cause data loss, or result in
lost connections.
– You have installed all networking software that is necessary for your network environment.
Check with your LAN administrator for the necessary networking software.
130 User Guide