Server fails to boot, all DIMM LEDs illuminate amber, ....

...the health LED is blinking red, the system emits continuous beeps, and an entry is logged to the Integrated Management Log (IML)

Possible cause: The server is an HP ProLiant G6 server with 5500-series Xeon processors installed. The DIMMs are not installed according to the server requirements.

Action: Be sure the memory is the correct type for the server and is installed according to the server requirements.

• Do not mix Unbuffered and Registered PC3 DIMMs.
• Populate DIMM slots for a processor only if the processor is installed.
• If Unbuffered DIMMs are installed, each channel supports a maximum of two DIMMs.
• If quad-rank DIMMs are installed for a processor, a maximum of two DIMMs can be installed on each channel for that processor.
• If a channel contains quad-rank DIMMs, the quad-rank DIMM must be installed first on that channel.

For more information, see the server documentation on the HP website.

If the system is configured with HP iLO 2 Firmware version 1.75, the IML message reports the following message:

Uncorrectable Memory Error (Module Unknown)

This does NOT indicate a failed DIMM; this only indicates a DIMM configuration error.

If the system is configured with HP iLO 2 Firmware version 1.77 or later, the IML message reports the following message:

Memory Configuration Error: System boot halted

For more information, see the server documentation on the HP website.