HP Compaq Pro 4300 Maintenance And Service Manual page 119

Cursor will not move using the
Cause
The Num Lock key is turned on.
There is no sound or sound volume is too low.
Cause
System volume may be set low or muted.
Cannot remove computer cover or access panel.
Cause
Smart Cover Lock, featured on some computers, is locked.
Poor performance.
Cause
Processor is too hot.
Hard drive is full.
Low on memory.
Hard drive fragmented.
Program previously accessed did not release reserved
memory back to the system.
arrow keys on the keypad.
Solution
Press the Num Lock key. The Num Lock light must be off if
you want to use the arrow keys on the keypad. You can also
disable or enable the Num Lock
Advanced > Device Options.
Solution
1. Check the Computer Setup settings to make sure the
internal system speaker is not muted (this setting does
not affect the external speakers).
2. Make sure the external speakers are properly
connected and powered on and that the speakers'
volume control is set correctly.
3. Use the system volume control available in the
operating system to make sure the speakers are not
muted or to increase the volume.
Solution
Unlock the Smart Cover Lock using Computer Setup.
In case of forgotten password, power loss, or computer
malfunction, you must manually disable the Smart Cover
lock . A key to unlock the Smart Cover Lock is not available
from HP. Keys are typically available from a hardware store.
Solution
1. Make sure airflow to the computer is not blocked. Leave
a 10.2-cm (4-inch) clearance on all vented sides of the
computer and above the monitor to permit the required
airflow.
2. Make sure fans are connected and working properly
(some fans only operate when needed).
3. Make sure the processor heat sink is installed properly.
Transfer data from the hard drive to create more space on
the hard drive.
Add more memory.
Defragment hard drive.
Restart the computer.
Solving General Problems 111
key in Computer Setup at