CMX4GX3M2A1600C8 on P55-GD85 unstable

[HenkB]

Hello,

 

Is there anybody (already) who can advise me on the settings for a CMX4GX3M2A1600C8 on an MSI P55-GD85 motherboard? I have been testing it for a week now, stability has become a lot better but it is still not good. With irregular intervals the system hangs, sometimes it needs two or three attempts to boot and I still get an occasional BSOD.

 

My current settings are:

Motherboard Fail-Safe Defaults, then changed DRAM timing to 1T 9-9-9-24, 1333 MHz, and DRAM voltage to 1.65V

 

I tried to find information on the Corsair website (e.g. Memory Finder) but I think the motherboard is still too new...

 

Thanks,

Henk Barreveld

[cashman]

Henk,

 

I'm having similar issues and have the same RAM albeit the C9 version rather than the C8 you have.

 

I have been told to run it at 2T rather than 1T. I have also been told to update my boards BIOS.

 

Also, shouldn't you be running your RAM at 1600mhz?

[RAM GUY]

The modules should be set to 8-8-8-24(CAS - tRCD - tRP - tRAS) and the memory voltage to 1.65v. Once those are set go ahead and adjust the memory frequency to 1600MHz.

[HenkB]

Thank you!

 

If I remember correctly, the settings 8-8-8-24 / 1600MHz / 1.65V was the first combination I tried after the motherboard's defaults failed. Those settings were not stable either.

 

Never mind, I tried again. Result: another system freeze within 10 minutes.

 

In the meantime I had noticed that the SPD values that CPU-Z shows for the XMP-1600, a Command Rate 2T is specified. So far I have all the time been using 1T, which is the BIOS default.

 

Does it make sense changing the Command Rate? Do you have other suggestions?

 

Thanks again for your help!

[RAM GUY]

Yes, please try changing the command rate if you are still having issues we can go ahead and replace the kit.

[HenkB]

Hello Ram Guy,

 

Thanks again. This is interesting -- well, for me at least.

 

I changed the settings to 8-8-8-24-2T / 1600MHz / 1.65V, as you advised. No problems. I ran two copies of Stress Prime 2004 for some 12 hours without any errors, I ran the MSI Afterburner software a few times, I ran 3DMark06 and PCMark Vantage.

 

No problems.

 

In the meantime I had also found on this forum that slightly increasing the QPI voltage might help. Even though I use only two of the four memory slots, I thought I should try this out. So I changed the settings back to 8-8-8-24-1T / 1600MHz / 1.65V, but this time I also changed the "CPU VTT" (as it is called by my CMOS Setup Utility) from the default 1.097V to 1.160V.

 

Ran the same tests again (Stress Prime 2004 "only" some six hours, this time), No problems! I only experienced a single freeze of the screen, which automatically recovered: "Display driver amdkmdap stopped responding and has successfully recovered" in the Event Log. This could be memory-related, but also not. Please note that during this freeze I was still able to access the computer from another computer through file-sharing.

 

This is similar to what I experienced in the beginning, but then it happened much more frequently and often there was also no automatic recovery.

 

So what do you think I should do? Be happy with the 8-8-8-24-2T / 1600MHz / 1.65V settings, or may there be a purpose in some further experiments?

 

In any case, the way matters are developing is positive enough. I currently expect that it will not be necessary to make use of your kind offer to replace the memory.