F3-12800CL7D-4GBECO unstable at spec voltage

[iamjohngalt]

I'm using 2x2GB F3-12800CL7D-4GBECO on a Gigbyte 890XA-UD3 mobo with a Phenom II 555 BE CPU.
I set the memory to 1600MHz 7-8-7-24 at 1.32v and 1.42v (Giga won't do 1.35v)
It was not stable enough to run windows XP.
It did stabilize at 1.52v (apparently after a 30 minute ORTHOS stress test.)

I bought this memory because of its specs at low voltage.
Is there something special I need to do to get those specs, or are these sticks faulty?
I did a web search for answers but did not find one.
Is there a Gskill rep that can help me pronto?
I am under time pressure to get this machine working.
If I have to get the sticks replaced by teh vendor I need to return them ASAP.
Thanks in advance.

[wevsspot]

I would attempt to set the X.M.P profile in BIOS first and let the board configure itself for the memory and see what happens.

[iamjohngalt]

The mobo uses AMD chips and CPU, not Intel, so I think it doesn't have an XMP profile. I do not see anything similar to XMP in the bios. The mobo auto mode sets the memory to 9-9-9-24 and 1333MHz.

[mrcmtl]

What if you leave it at 1.42V on the RAM and bump CPU/NB voltage to 1.2V

[wevsspot]

The mobo uses AMD chips and CPU, not Intel, so I think it doesn't have an XMP profile. I do not see anything similar to XMP in the bios. The mobo auto mode sets the memory to 9-9-9-24 and 1333MHz.

You're right. I stand corrected. I apologize for that error on my part.

[wevsspot]

.......bump CPU/NB voltage to 1.2V

On that board I think it's called the CPU NB VID Control

[iamjohngalt]

THe CPU NB VID control voltage is 1.2v as default.
I boosted CPU NB VID by .025v and lowered memory to 1.42v, ORTHOS test went for 7 sec and gave error.
I boosted CPU NB VID by .05v and lowered memory to 1.42v, and windows crashed to BSOD before I could start the test.
Thanks for trying guys. Seems like this is not the change that will help.
Any other ideas?
Anyone out there from GSkill that can help me with this?

[wevsspot]

John,

As a test, reduce memory frequency to 1333Mhz, leave CPU/NB voltage at 1.25 and DRAM Voltge at 1.32

Use the same memory timings (7-8-7-24 2T) and see if the board boots and it's stable.

Let us know the results.

Regards,

[GSKILL TECH]

That CPU does not fully support DDR3-1600 CL7. So you'll have to use CL8, or use a higher DRAM Voltage.

Thank you
GSKILL TECH

[iamjohngalt]

wevsspot,
It is stable after 30 min ORTHOS stress test at 1333 7-8-7-24-2t.

GSkill Tech has spoken. I guess there are no Phenom CPUs that "fully support" 1600.
At least I was unable to find any reference on the AMD website.

Guess its back to trading economy for speed.

[iamjohngalt]

Thanks to Gskill Tech for explaining.

[mrcmtl]

You could test stability at 1.5V. Phenom II do support 1600, but they need some tweaking.

[GSKILL TECH]

Right, they don't fully support DDR3-1600 "natively"

Thank you
GSKILL TECH

[zila]

John, these sticks are awesome. They run fine at 1600 on my rig. You just have to find what works best with your rig. Mine likes to be O/C to 1600.

[iamjohngalt]

Hi, zila,
Thanks for your input.
I am still testing them... now with a Phenom B97 cpu that I have on approval.
Its a 4 core very similar to a Phenom II 955, but without an unlocked multiplier.
It is overclocking to 3.69 Ghz at 1.4v and the memory was at 1531 8-8-8-24, last I tested.
I didn't see a way to tweak the memory a little higher in the BIOS without exceeding the stability of the cpu (or NB or something) at 230 FSB. Any advice on that?

Cheers.