BIOS not recognizing whole RAM

[bo.]

Hello everyone,

like the title says, I have got a problem with my computer not recognizing all of my installed RAM.
System:
i7-930 @ 2.8 GHz
Sapphire Pure Black X58 Board
12 GB Ripjaws(F3-12800-CL8T-6GBRM)
I had a tri-kit with 3x2GB modules for about one year and now bought another similar kit so that I got this 12 GB.

Now my problem is, that my BIOS and therefore windows is sometimes not recognizing all of this 12GB. Sometimes it's 6GB, then 8GB but most of the time either 4GB or the full 12GB of RAM. CPU-Z still showing all 6 slots installed and I don't see any difference between the slots.

Tried XMP-Profiles, but I read somewhere that this doesn't work with two kits. So I disabled it and tried DEFAULT settings, but still the same problem -> random amount of RAM.
Also reinstalled my CPU-Cooler because somebody said this could be a problem if it is fastened too hard and I switched the modules to some other slots. Board is brandnew (1 week) and I haven't got any ideas left.
Now I only have my original 6 GB installed in the right slots on the board (put in after the board's manual) but right at the moment I am writing this I only have 2GB instead of 6GB.

BIOS is newest version, Windows 7 64bit Professional

Thanks in advance and sorry for probably bad english

Greetings from germany

[Tradesman]

Try reseating all the sticks and ensuring the gold contacts on them are clean, a bit of dust or small fiber in there can screw thing up

[bo.]

Ok so I have blewn trough all the modules and the slots on the board. After that I reseated them in a different order, rebooted and got 4 out of 12 GB Ram.

[Tradesman]

Another possible that can cause problems is bent pins in the CPU socket or lint, dust in there, even having a bit of thermal compound seep onto the bottom of the CPU or into the socket. Could also try with one set and see what that does, using XMP...if all 6GB of the set show up then disable XMP, make sure the base timings and CR are correct, add the second set, again check that the base timings, etc are correct and from there add a little voltage to the DRAM and/or QPI/VTT (MC (memory Controller)) voltage

[bo.]

When I reinstalled my CPU-Cooler I checked the pins in the socket but there was no obvious damage. I cleaned the CPU and the cooler of the thermal compound, reapplied new one and fastened the screws slowly and not too much.
With only the first tri-set sticked in my PC the problem still persists. No matter if XMP activated or not.
As you said, I have also checked the timings and on "auto" is has been 8-8-8-20-2N. 20 was weird somehow because it should be 24 I think. But even when I changed it to 8-8-8-24 no difference.
Also I've tried to increase the voltages:
DIMM: 1.6V (default:1.5)
VTT: 1.275V (default: 1.2)
QPI VLL: 1.175 (default: 1.1)

With many reboots trying all these things it currently sticks to 8GB of RAM.
I don't know if it will help, but here's a screenshot of the CPU-Z screen showing the RAM and its settings.

[Tradesman]

Might check in msconfig and see if it's limiting the DRAM, Click Start, and in the search box type MSCONFIG , then hit enter, select the boot tab, then ADVANCED OPTIONS and make sure the MAXIMUM MEMORY box is unchecked.

[bo.]

Yeah it is unchecked. It's already in BIOS less than my 12 Gig.

[Tradesman]

If all the sticks test OK with memtest, would guess a problem with the mobo, any chance of having or borrowing another set of sticks to test with?

[bo.]

Another possible that can cause problems is bent pins in the CPU socket or lint, dust in there, even having a bit of thermal compound seep onto the bottom of the CPU or into the socket. Could also try with one set and see what that does, using XMP...if all 6GB of the set show up then disable XMP, make sure the base timings and CR are correct, add the second set, again check that the base timings, etc are correct and from there add a little voltage to the DRAM and/or QPI/VTT (MC (memory Controller)) voltage

So on friday I borrowed 4 GB RAM and it worked like it should.
After that I followed your instructions from above step by step and I don't know why, but it worked. When all 12 GB showed up I increased the voltages and set the frequency manually to 1600 MHz. It worked all the weekend without any problems. Really seems the RAM was underclocked on this board. Also memtest showed no errors so I'm quite happy.
Now I can try to overclock my CPU and maybe also the RAM a little more. Thank you very much for your help!

One final question:
What frequency/voltages do you think my model of the ripjaws can handle?

Greetings!

[Tradesman]

They are rated for 1600, so can try there with your combo 1333 might take less voltage to the NB and therefore less heat

[bo.]

Hello again,

I have to replay to this thread again because the problme still persists. This morning when I booted my PC the BIOS only showed 4GB and I instantly stopped the boot process with the power button. I booted again and had my 12GB back. Didn't think much more about it then. Now again I've booted my PC and only got 8GB...
So, the problem is still here and I really don't know what to do.

Any further advice?

[Tradesman]

Do you have the latest BIOS, if not try that, if still no joy try the DRAM at 1.65 and raise QPIVTT + .06

[bo.]

Yes I have got the latest BIOS.
The voltages already have been: DRAM 1.65V and VTT 1.35V, which is near the maximum Intel is allowing for it I think.

[Tradesman]

Will see if I can get GSkill to take a look today or Thur

[bo.]

As the new week begins, I just wanted to ask, if there is any news from you?
Here everything is still the same, currently only 4 gigs of RAM. This afternoon I had 12 before I rebooted.