Compaq Deskpro EN Series Maintenance & Service Manual page 147

Picture is broken up, rolls,
jitters, or blinks.
Screen goes blank.
Monitor overheats.
Cursor will not move using
the arrow keys on the
numeric keypad.
Memory
Problem
Out of Memory error.
Memory count during
POST is wrong.
Insufficient memory error
during operation.
System won't boot or does
not function properly after
installing additional memory
modules.
F-4 Troubleshooting Without Diagnostics
1. Be sure the monitor cable is securely connected to the computer.
2. In a 2-monitor system or if another monitor is in close proximity, be
sure the monitors are not interfering with each other's magnetic field by
moving them apart.
A screen blanking utility may be installed or energy saver features are
enabled. Press any key or type password.
There is not enough ventilation space for proper airflow. Leave at least 3 -
inches (7.6 -cm) of ventilation space. Also, be sure there is nothing on top
of the monitor to obstruct air flow.
Num Lock key is on. Press the Num Lock key. The Num Lock light should
not be on when you want to use the arrow keys.
Possible Solution
1. In Windows NT, run Performance Monitor. At the Start menu, highlight
Programs and select Administrator Tools. In Windows 95, run
Resource Meter. At the Start menu, highlight Programs, select
Accessories, then select System Tools.
2. Computer has run out of memory to run the application. Check the
application documentation to determine the memory requirements.
Memory modules may not be installed correctly. Check that the memory
modules have been installed correctly, then run the Configuration utility.
1. Too many Terminate and Stay Resident programs (TSRs) are
installed. Delete any unnecessary TSRs.
2. The computer has run out of memory for the application. Check the
memory requirements for the application or add more memory to the
computer.
Memory module is not correct type or speed grade for the system.
Replace module with an industry standard, SPD-compliant 168-pin
synchronous dynamic random access memory (SDRAM) DIMM that
meets the following criteria (if you do not know the system bus speed, run
Computer Setup to determine it):
66 MHz Bus Speed
•
Rated for 66 MHz or faster operation
•
Has an access time (CLK to Q) of 9
ns or less
•
Cycle time of 15 ns
•
Supports CAS latency of 2 or 3
operation
100 MHz Bus Speed
•
Rated for 100 MHz or faster
operation
•
Has an access time (CLK to
Q) of 6 ns or less
•
Cycle time of 10 ns
•
Supports CAS latency of 2
or 3 operation