How to tell whether ECC (memory) is enabled?

Thomas Zander thomas.e.zander at
Sat Nov 6 16:04:30 UTC 2010

On Fri, Nov 5, 2010 at 20:54, C. P. Ghost <cpghost at> wrote:

> Have you tried 'dmidecode' (as run), from the port sysutils/dmidecode?

I have actually, but the output is somewhat unexpected (besides the
fact that there are cases in which its report do not match reality.
The manpage says "often".).

In my box in question for example, dmidecode reports about the memory

        Error Detecting Method: 64-bit ECC
        Error Correcting Capabilities:
        Supported Memory Types:
        Memory Module Voltage: 2.9 V
        Associated Memory Slots: 4
        Enabled Error Correcting Capabilities: None

That seems wrong in at least two positions: First, it clearly lacks
"ECC" in the "Supported Memory Types" section, and for its voltage I
was expecting 1.8 V, not 2.9 V.
The output concerning the memory modules itself is also unexpected.
Just to pick one:

        Socket Designation: A0
        Bank Connections: 0 1
        Current Speed: 5 ns
        Type: DIMM
        Installed Size: 2048 MB (Double-bank Connection)
        Enabled Size: 2048 MB (Double-bank Connection)
        Error Status: OK

While it is correct about the size, I would expect "Type: ECC DIMM" here.
Therefore, I don't tend to trust its output, and a kernel message
stating "I am running on ECC memory" would be lovely :-)


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