Is ECC working?

[jon_2112]

There doesn't seem to be any surefire way to tell whether ECC is enabled on my system or not. DMIdecode shows a total width of 72 bits and data width of 64 bits, but it also says Error Correction Type: None.

This is on an Asus P9D-MV with supported memory (I have 2x4GB Samsung M391B5273DH0-YH9 ECC RAM). I have a Pentium G3250 (supports ECC, according to Intel) CPU.

Here's the dmidecode output:

# dmidecode 3.0
Scanning /dev/mem for entry point.
SMBIOS 2.7 present.

Handle 0x003E, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x003F
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: DIMM
Set: None
Locator: DIMM_A1
Bank Locator: BANK 0
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: [Empty]
Serial Number: [Empty]
Asset Tag: 9876543210
Part Number: [Empty]
Rank: Unknown
Configured Clock Speed: Unknown

Handle 0x003F, DMI type 16, 23 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 32 GB
Error Information Handle: Not Provided
Number Of Devices: 4

Handle 0x0040, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x003F
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: DIMM
Set: None
Locator: DIMM_A2
Bank Locator: BANK 1
Type: DDR3
Type Detail: Synchronous
Speed: 1333 MHz
Manufacturer: Samsung
Serial Number: 86C518E9
Asset Tag: 9876543210
Part Number: M391B5273DH0-YH9
Rank: 2
Configured Clock Speed: 1333 MHz

Handle 0x0042, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x003F
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: DIMM
Set: None
Locator: DIMM_B1
Bank Locator: BANK 2
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: [Empty]
Serial Number: [Empty]
Asset Tag: 9876543210
Part Number: [Empty]
Rank: Unknown
Configured Clock Speed: Unknown

Handle 0x0043, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x003F
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: DIMM
Set: None
Locator: DIMM_B2
Bank Locator: BANK 3
Type: DDR3
Type Detail: Synchronous
Speed: 1333 MHz
Manufacturer: Samsung
Serial Number: 86C51881
Asset Tag: 9876543210
Part Number: M391B5273DH0-YH9
Rank: 2
Configured Clock Speed: 1333 MHz

 

[ChriZ]

Are you sure that you have posted the correct motherboard model...?
Because I found no Asus P5D-MV, only an Asus P5D-VM, and even so that one is a c2d mobo with non ECC DDR2 Ram support....

 

[jon_2112]

Typo, sorry. P9D-MV. Intel C222 chipset.

 

[ChriZ]

Well, the P9D-MV seems like a "proper" choice...
According to the specs, your combination of parts should result in working ECC.
And although I don't personally trust dmidecode much, the fact that it reports none in Error Correction Type is disconcerting..
The only thing I can think of is to check in your BIOS for a possible setting regarding enabling/disabling ECC support...

 

[jon_2112]

Here's the output from the "ecc_check" program I've seen referenced a few times:
5004-5007h: 10 0 63 0
5008-500Bh: 10 0 63 0

The 0 would seem to indicate ECC is not enabled. I've spent a ton of time in the BIOS and nothing. There's apparently some controversy over the Intel ARK not necessarily being accurate, as it has said some i3 processors have ECC support but actually don't. Then there's this thread which lists a bunch of Celeron and Pentium processors that support ECC, but my G3250 isn't listed (though the G3240 is): https://communities.intel.com/message/283354#283354

Maybe I just need to buy a G3240, or a Xeon, and see what happens. Sigh.

 

[ChriZ]

Your CPU does support ECC according to intel ark
Something else is wrong... Perhaps you can try to contact Asus.

 

[cyberjock]

Its possible that Asus isn't supporting the ECC feature. It's one of the reasons why I advocate so much for using what we recommend (Supermicro MB, Intel CPU, and ECC RAM) because you are banking on the fact that Supermicro won't screw up and somehow disable ECC. Asus, being the manufacturer that they are (primarily desktops) don't have much vested interested in ECC working. Asus has virtually no market for servers, so ECC being a required functional feature is not a guaranteed thing. If Supermicro fubared their ECC functionality, tons of companies all over the place would be in a panic. ;)

 

[ChriZ]

Sadly, it is true that many motherboard manufacturers with desktop as their main target, may claim ECC support, but in many cases they merely mean that using ECC RAM won't result in errors; they will work but without using ECC functionality.
What I find strange, though, is that this mobo seems like a proper one - it seems that it is even lacking audio, something common is server motherboards.
Perhaps you can try to check for any BIOS updates that may address this ECC issue...

 

[jon_2112]

I suppose you guys are right. I swapped to a Xeon and still nothing, so I swapped in a Supermicro X10SLL motherboard instead. Now ECC is definitely enabled:

Code:

[root@mickey] ~# dmidecode -t 16
# dmidecode 3.0
Scanning /dev/mem for entry point.
SMBIOS 2.7 present.

Handle 0x004A, DMI type 16, 23 bytes
Physical Memory Array
        Location: System Board Or Motherboard
        Use: System Memory
        Error Correction Type: Single-bit ECC
        Maximum Capacity: 32 GB
        Error Information Handle: Not Provided
        Number Of Devices: 4

[root@mickey] ~# ecc_check
5004-5007h: 20 0 63 3
5008-500Bh: 20 0 63 3