HP dx2420 - Microtower PC Troubleshooting Manual page 17

Computer date and time display is incorrect.
Cause
RTC (real-time clock) battery may need to be replaced.
NOTE: Connecting the computer to a live AC outlet prolongs
the life of the RTC battery.
Cursor will not move using the arrow keys on the keypad.
Cause
The Num Lock
Poor performance is experienced.
Cause
Processor is hot.
Hard drive is full.
Low on memory.
Hard drive fragmented.
Program previously accessed did not release reserved
memory back to the system.
Virus resident on the hard drive.
Too many applications running.
ENWW
key may be on.
Solution
First, reset the date and time under Control Panel (Computer
Setup can also be used to update the RTC date and time). If
the problem persists, replace the RTC battery. See the
Hardware Reference Guide for instructions on installing a new
battery, or contact an authorized dealer or reseller for RTC
battery replacement.
Solution
Press the Num Lock key. The Num Lock light should not be on
if you want to use the arrow
disabled (or enabled) in Computer Setup.
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 heatsink 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.
Run virus protection program.
1. Close unnecessary applications to free up memory.
Some applications run in the background and can be
closed by right-clicking on their corresponding icons in the
task tray. To prevent these applications from launching at
startup, go to Start > Run (Microsoft Windows XP) or
Start > All Programs > Accessories > Run (Microsoft
Windows Vista) and type msconfig. On the Startup tab
of the System Configuration Utility, uncheck applications
that you do not want to launch automatically.
CAUTION: Do not prevent applications from launching
at startup that are required for proper system operation.
2. Add more memory.
Solving General Problems
keys. The Num Lock key can be
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