GA-X58A-UD5 and Dominator 1600 12+12 GB: only 20 GB enabled

[ikas]

Hi,

I built my rig about 1.5 years back with 12 GB of CMP12GX3M3A1600C9 memory kit.
I recently bought another 12 GB of the same in the hopes to up my total RAM to 24 GB.
Alas.. the system only shows 16 GB if i plug in all the memory modules.

I am able to get 20 GB enabled if I remove the module from slot 6. And the memory is running at 1.5V 1033 speed.

I was able to get 24 GB enabled once, but on the subsequence reboot, it didnt work.

I read similar problems on other threads and tried re-seating the CPU, reshuffling the modules in the slots. But they dont work.

I am not too sure about setting the memory voltage and QPI settings... any help to get this up to 24 GB working would be appreciated.

Thanks.

EDIT: i went through this thread http://forum.giga-byte.co.uk/index.php/topic,10203.0.html and am not sure if these are not "matching sets"?

MoBo revision 2.0, BIOS version FB

[MarkJohnson]

No, they are not matching sticks.  Matching sticks will all come together in a single package.  Plus you bought the second set some time later and they may have changed memory types/brands to make matters worse.

Try each set individually ans see if they show up properly.

You just may have a bad chip or two.

There is also a newer bios that may add more memory compatibility and allow these to work.

Try using the, "Load system defaults" for memory timings.  I know the X58 didn't show much improvement on performance with faster memory.  The higher speeds can put a strain on the memory controller otherwise, plus the extra memory sticks put even a greater load on the controller and be causing you issues.

You may be wise to return current sticks, sell old sticks then buy a matched set of 3x8GB sticks.  If your board supports 8GB sticks, which it should by now.  I know the X58s had a weak memory controller.  Going from 1 memory controller and 4 sticks max, to 3 memory controllers and 6 stick max. was a big change.


Remember the x58 default memory speed is 1066.  Any higher may require overclocking the memory.  But first get them all working at 1066 or even test 800 with all 6 stick if failure occurs.

[ikas]

I am getting unreliable results on my mobo.
I tried the "Load system defaults" and it didnt have any effect on this issue.
I tried reducing the SPD to 6 [800 mhz memory speed] and for a couple of boots, I was able to see and use all the 24 GB.
I had enabled the Profile1, and reduced the SPD to 6. But after a couple of boots, it started recognizing only 12 GB.

I removed the module from slot 6, and disabled the XMP profile1, but manually set the SPD to 12 [1600 mem speed] and this works consistently.

So I am really confused here.

[ikas]

I believe I have a faulty module.

I downloaded Memtest86_4.0a.iso, burnt it to a 1 GB USB flash drive using rufus_v1.2.0.exe and rebooted through USB to have the memtest running.
I tested the 20GB for 1 cycle and it passed without errors.
I then removed all of the modules and inserted the one module i suspected into slot 1. But the boot sequence never gets past the error code C1 [DRAM check]


I tried the rest of the five modules in various slot combinations and they all boot fine to 20 GB @ 1600 Mhz.
The onboard LED for CPU glows if Profile1 [XMP] is not enabled, but the SPD is set to 12 [1600Mhz]. This does not happen if the profile1 is enabled.

Is there any other way I can know for sure the module is at fault ?

Thank you, MarkJohnson, for your input.

[MarkJohnson]

what happens if you try a different stick in that one slot?

check questionable stick in other slots by itself.

check other sticks as well for errors one at a time.

[ikas]

I did try another module in the same slot and it works.
Will do the other things as suggested.