Memory Speed Reporting Issue

[WonkeyDonkey]

I've been looking into a memory speed reporting issue and everything is now pointing towards either Chimera or OSX itself.

The motherboard in question is the Asrock Z87E-ITX.

The memory installed is Corsair Vengeance Pro Silver 1866 CL9.

The issue is that when booted into OSX the System Information/Memory page shows one stick running correctly at 1866 but the second running at 1333.

All bios settings are at default with XMP selected in the bios.

With the same settings on Windows 7 it shows both sticks operating correctly, using CPU-Z.

With the same settings in Linux it shows both sticks correctly running at 1866 also.

I've been having several discussions with Asrock about this and they are unable to replicate the issue at all.

Memory slot info in OSX :



I know it can be changed cosmetically through smbios.plist, but is there any chance this can be fixed properly ?

 

[MacMan]

The values in Chimera are based on what the BIOS is reporting.

To verify the values run bdmesg in terminal and look to see what is reported for each Type: 17 MemoryDevice.

 

[WonkeyDonkey]

The values in Chimera are based on what the BIOS is reporting.

To verify the values run bdmesg in terminal and look to see what is reported for each Type: 17 MemoryDevice.

bdmesg | grep 17 shows this :

Type: 17, Length: 34, Handle: 0xf
Type: 17, Length: 34, Handle: 0x11

Which doesnt mean a lot to me really....

 

[MacMan]

You need to look at the details for each of those entries to see what it's reporting for the memory speed.

 

[WonkeyDonkey]

You need to look at the details for each of those entries to see what it's reporting for the memory speed.

I see this in bdmesg :

Type: 17, Length: 34, Handle: 0xf
MemoryDevice:
deviceLocator: ChannelA-DIMM0
bankLocator: BANK 0
memoryType: DDR3
memorySpeed: 1867MHz
manufacturer: Corsair
serialNumber: 00000000
assetTag: 9876543210
partNumber: CMY16GX3M2A1866C9

Type: 20, Length: 35, Handle: 0x10
Type: 17, Length: 34, Handle: 0x11
MemoryDevice:
deviceLocator: ChannelB-DIMM0
bankLocator: BANK 2
memoryType: DDR3
memorySpeed: 1333MHz
manufacturer: Corsair
serialNumber: 00000000
assetTag: 9876543210
partNumber: CMY16GX3M2A1866C9

dmesg in Linux reports just fine though, also CPU-Z in Windows shows it correctly as well.

 

[MacMan]

It looks like your 2nd memory stick has been programed incorrectly as Chimera has read it's speed as:

memorySpeed: 1333MHz

OS X uses the same method for reporting RAM speed as Chimera.

You can verify this using "smbios tools" which are available for OS X and Linux.

 

[WonkeyDonkey]

It looks like your 2nd memory stick has been programed incorrectly as Chimera has read it's speed as:

memorySpeed: 1333MHz

OS X uses the same method for reporting RAM speed as Chimera.

You can verify this using "smbios tools" which are available for OS X and Linux.

Are we talking the likes of dmidecode here then or are there specific or recommended tools for the job ?

Searching for smbios tools throws up some rather generic and dated results.

 

[MacMan]

You will need smbios-reader to dump the smbios into a file and then use dmidecode to make it readable. Or at least in the version I have used in the past.

 

[WonkeyDonkey]

You will need smbios-reader to dump the smbios into a file and then use dmidecode to make it readable. Or at least in the version I have used in the past.

Well the latest version of DarwinDumper does a nice job of dmidecode and all manner of other goodies.

It still shows the first slot running at 1866 and the second at 1333.

I swapped the memory sticks around, but its still exactly the same which rules out the possibility of the sticks themselves being faulty.

Does this infer a bios fault or hardware fault perhaps ?

 

[WonkeyDonkey]

Cracked it, I think! Finally!

Scanning through the results of the dmidecode, I see these 2 entries for the memory :

Memory Device
Array Handle: 0x000E
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 8192 MB
Form Factor: DIMM
Set: None
Locator: ChannelA-DIMM0
Bank Locator: BANK 0
Type: DDR3
Type Detail: Synchronous
Speed: 1867 MHz (0.5 ns)
Manufacturer: Corsair
Serial Number: 00000000
Asset Tag: 9876543210
Part Number: CMY16GX3M2A1866C9
Rank: 2
Configured Clock Speed: 1867 MHz (0.5 ns)

Memory Device
Array Handle: 0x000E
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 8192 MB
Form Factor: DIMM
Set: None
Locator: ChannelB-DIMM0
Bank Locator: BANK 2
Type: DDR3
Type Detail: Synchronous
Speed: 1333 MHz (0.8 ns)
Manufacturer: Corsair
Serial Number: 00000000
Asset Tag: 9876543210
Part Number: CMY16GX3M2A1866C9
Rank: 2
Configured Clock Speed: 1867 MHz (0.5 ns)

The last line on both of these entries shows the 'Configured Clock Speed' as 1867 (This means the XMP Information is being read and used correctly).

But look 7 lines up from the bottom of each entry; the top one says 'Speed: 1867 MHz (0.5 ns)

Whereas the bottom one says 'Speed: 1333 MHz (0.8 ns)

This is surely the culprit.

Now since Windows and Linux report both sticks at the correct speeds, Im guessing they report using the 'Configured Clock Speed', and that Chimera/Chameleon/OSX report using the 'Speed:' value instead, which corresponds with what I am seeing in the Memory section of System Information.

Since all other values above are identical, this surely has to be the cause of it ?

It certainly explains all the results I have had with this issue from day one.

Any thoughts ?

/removesSherlockHatAndPipe