|It is important to make sure that you are using the correct part numbers when selecting computer memory. Any third party memory must be a direct replacement for the Lenovo option part number or replacement (FRU) number.
Note: Some of the following steps may not apply to your system.
- Remove any non-standard or non-original branded memory from the computer.
- Using incompatible memory is the most common reason memory upgrades do not work.
- While incompatible memory may work to some extent, it can lead to unpredictable system behavior including data corruption and poor system performance including blue screen stops and intermittent lockups.
- Memory installed after receipt of the system should be verified as fully compatible with the system.
- Reset the remaining memory modules firmly in their slots.
- Memory and other components frequently become dislodged when other work is done inside the system or when the system is moved from one location to another.
- Ensure that all memory is properly configured, properly installed, and is designed with the correct technology.
- To detect dual memory mode, the Power on self test setting in the System Configuration Utility must be set to "Enhanced".
- To enable dual memory mode, both slots (slots 1 and 3, or slots 2 and 4) of a channel (channel A or B) must be populated. Memory modules must be oriented in the correct slots.
- Dual inline memory technologies must match exactly. Refer to the "Installing memory" section of the system's User Guide for additional guidance.
- A startup beep code of 1-3 typically indicates a memory problem. Go to Troubleshooting startup or booting issues to investigate beep codes.
- Install one piece of memory at a time, if possible, trying the different memory slots.
- Replace the suspect memory with a known good memory module. If the memory still fails, the system board memory slot may be defective.
- Move the suspect memory to a known good slot, several slots, or another computer. If the memory is still not recognized in known good slots, the memory is probably the cause of the failure.
- Use Lenovo Diagostics Software.
- Check to make sure the currently installed BIOS is the latest available.
Note: The initial memory count on some computers may indicate 1MB less than expected. Some machines use at least 1MB of memory for video.