Either DIMM works, 2 DIMMs together fail

[Jeffowl]

System:
Proc: i5-750
MB: GA-P55A-UD3
BIOS: F8
RAM: F3-12800CL9D-4GBRL
Video: Gigabyte GeForce GTX-260
PSU: Corsair 750TX

Was running for about a month with both DIMMs installed, one in each bank, running at 1333, 9-9-9-24.

Started getting BSOD.
Memtest86+ v.4.10 indicates failures, mostly in test #5. Mostly in the same memory region, almost always the same bit, regardless of the address.

I tried to isolate it to one DIMM, or one bank, but either DIMM installed in either bank by itself will pass.

Running with XMP at 1600 does not change the results. A single always passes, two always fail.

I tried increasing the DRAM voltage to 1.58v. It had no effect on the results.

Any thoughts on this?

[GSKILL TECH]

Very odd. Have you tried the other two slots?

Thank you
GSKILL TECH

[Jeffowl]

Very odd. Have you tried the other two slots?

Thank you
GSKILL TECH

I didn't try using sockets 2 and 4. The manual says to use 1 and 3 if only using 2 DIMMs in a dual channel memory configuration. I could try it.

I did try both in the same bank, that failed.

[Jeffowl]

I tried sockets 2 and 4 and the system wouldn't even come up.

[Cey]

arranged tract

On Lynnfield Systems, DIMMSlot1 must be used following the user manual.

I had the same problems, and sovled it:

Check out http://www.gskill.us/forum/showthrea...3538#post23538

(Try loosening the screws of your CPU cooler if they could be screwed too tightly)

[Jeffowl]

Interesting idea. I'm skeptical because it's was working for a month without me changing the tension on the screws. But since nothing else seems to be working right now, I may just give it a try. I could also go back to the stock cooler, which doesn't use a backing plate at all.

[Cey]

My system also went fine for many months. Just an idea, it helped me, so might help you too

You don't have to get back to the stock cooler. My Mugen 2 is clamped well enough on the mainboard even if the screws are not fastend that tightly. (I really tightened them until I couldn't screw them anymore further)

[Jeffowl]

Cey,

I tried loosening it up. It doesn't seem to have changed anything. Thanks for the idea though.

[Cey]

Hm =/
If you google a little bit, some people have experienced improvements by remounting the CPU on the socket (and checking if any pins of the socket look strange or are damaged), sometimes it also helped to remove the I/O shield.
Well, there could be many sources of your problem, maybe the g.skill technicians have better ideas.
Good luck!

[Jeffowl]

I was able to borrow some brand "S" memory with similar, but not exactly the same, specs. I installed it in a normal dual channel configuration and it seems to work just fine. It works at 1333 or 1600(XMP).

[vipse]

I am having the same problem, random bsod on two dimms both plugged in, and very stable on just plug in just one, either one. It's not the same as other described "cold start". My crashes happen all the time, no matter cold start or not.

CPU: Phantom X2 555
Mem: F3-10666CL9D-4GBNQ
MOBO: Gigabyte GA-770TA-UD3
Graphics: Radeon 5750 512MB

I have tried increase mem voltage, decrease mem speed to 1066, none of them worked.
Now I am not sure if I should RMA the ram or blame the memory controller in the CPU.
If I RMA them, will gskill take them, because they may find out the dimms work fine?

[GSKILL TECH]

Not a problem, simply send them in for new replacements and the new set should work just fine.

Thank you
GSKILL TECH

[glennjames71]

I had exactly the same problem you described. I have spent weeks trouble-shooting trying every combination of speed, timing CPU & NB voltages, one stick of ram, two sticks etc but to no avail.

Fortunately, I got the opportunity to test the RAM in another sytem (Dell Opti 780). I ran Prime95 and memtest for over an hour each without any errors in dual channel. Not a conclusive test but a pretty good indicator that the RAM was fine and the problem must be elsewhere.

When it came to putting the RAM back in to my system, I gave the gold edge connectors a quick rub with a pencil eraser ( an old trick from back in the day) and had a final go at dual channel. Guess what? I have been running in dual channel at 16000 8-8-8-24-34-1N for a week now without a single BSOD!

I cannot explain how or why my system is working again but it is. There were only three things that occured inbetween my system not working and working: -

1. Removed RAM from my system for 12 hours - maybe this allowed a cap or something to discharge on the motherboard?

2. Ran the RAM at SPD speeds/timings on another rig - is any of the SPD data area writable?

3. Rubbed the edge connectors of the RAM with a pencil eraser - the connectors did not looked tarnished at a glance and the RAM is only 8 months old but there did appear to be a subtle difference when compared to the stick that I had not rubbed yet.

I don't know of any of the above will help you as it all sounds pretty incredible but, seriously, this has fixed my problem and I haven't had a single blip in dual channel since.