Compaq Compaq Evo Desktop, 177620-006 manual Solving Memory Problems

Troubleshooting Without Diagnostics

Solving Memory Problems

If you encounter memory problems, some common causes and solutions are listed in the following table.

ÄCAUTION: Some models support ECC memory and non-ECC memory. Other models support only non-ECC memory. For those systems that do support ECC memory, Compaq does not support mixing ECC and non-ECC memory. Doing so will cause the system to blink the Num Lock LED on non-USB keyboards continuously and, if a speaker

is installed in the system, there will be a short beep followed by 2 long beeps. In addition, the system will not boot the operating system.

✎See the “Interpreting the Diagnostic Lights” section of the Getting Started guide to identify other possible memory problems.

Solving Memory Problems

Problem Cause Solution

System won’t boot or does not function properly after installing additional memory modules.

Memory module is not the correct type or speed grade for the system or the new memory module is not seated properly.

Replace module with the correct industry-standard device for your computer.

On some models, ECC and non-ECC memory modules cannot be mixed.

On a single-channel Rambus memory system, the RIMM sockets may be empty.

Check to see that all RIMM sockets contain either RIMMs or CRIMMs and replace them if needed.

On dual-channel Rambus memory system, RIMM pairs may not be identical.

RIMMs must be added in pairs that are identical in speed, number of devices, and manufacturer. If the RIMM pairs are not identical, replace them.

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