B-Die DRAM OC issues

[dmt_taran]

I've never payed much attention to DRAM OC (XMP or simple clock raise aat 1-2 steps), but now I was itching to hike the system to the max.
But I've bumped into concrete wall.

So, the specs are 8700K, x hero, gskill trident 2x16GB B-die dual rank 14-14-14-34 1.35V 3000 mhz ram.

I've started from available on the market maximum - that is 4000 CL19 2x16 ram. I've checked primary timings, raised vSA/vIO to 1.30V (thus, 1.35 aftre boot), RAM was at 1.45V, that is more than factory 4000 mhz requires. Boot failed.
Then I've took moderate approach, decreased target frequency to 3600MHz, 17-19-39, vSA/vIO left the same, vRAM - 1.4V. I wasn't able to boot.
I've checked all things couple more times, raised vRAM to 1.45, kicked CL20 timings, raised vSA/vIO to 1.38V - nothing helped.

In both situations, boot stucked at RAM initialization with Qcode 6A.

Tried to push RAM at 3200 MHz withing factory settings - system does boot, but for veeeeery long time + it is not stable at all - numerous errors, application crashes, etc.

What am I doing wrong?

[NemesisChild]

dmt.taran wrote:
Yup, thought mine could do aswell.
For now, all previous bootable set-ups, unfortunately, were unstable, so I didn't achieved any stable result, exept one I'm testing right now.
maximus tweak is on 1

So, I'll mark it up: 3200MHz, CL14, Command rate 2T, 1.4V, vSA+IO 1.20V

Though, I was unable to force the thing boot with 1T command rate, only in stock 3000MHz. In any other OC case, it just stucks at RAM initialization with bF (6F) code.


P.S. What's the better option for ram oc test? For such purpose I've always used AIDA, but I can see people utilizing this "testmem" thing....though I don't really like it, looks glitchy. But if it is more effective, why not.

Your SA voltage is high. I've tested numerous memory configurations. Best for me has been VCCIO (1.15v) and SA (1.20v).

Keep the CR at 2T for better overall stability. You only get a marginal hike in performance with 1T anyways.

[chevell65]

According to G.SKILL the maximum rated memory speed with a 16GBx2 kit for the Z370 Maximus X Hero is 3733MHz CAS 17. http://www.gskill.com/en/product/f4-3733c17d-32gtzr. I'm sure this is at the 2T command rate as well.

These G.SKILL memory kits are tested at XMP for each particular board, not just a general test with a particular chipset like everyone else does. The QVL at G.SKILL appears to be the most accurate one compared to anyone else.

[dmt_taran]

chevell65 wrote:
According to G.SKILL the maximum rated memory speed with a 16GBx2 kit for the Z370 Maximus X Hero is 3733MHz CAS 17. http://www.gskill.com/en/product/f4-3733c17d-32gtzr. I'm sure this is at the 2T command rate as well.

These G.SKILL memory kits are tested at XMP for each particular board, not just a general test with a particular chipset like everyone else does. The QVL at G.SKILL appears to be the most accurate one compared to anyone else.

They also have these ones http://www.gskill.com/en/product/f4-4000c19d-32gtzsw
I suppose, they use identical chips for all those low latency, high speed kits

I was able to boot with 1T command rate only at 3000MHz. No luck with any other option 😞

[dmt_taran]

I'm giving up!
I was unable to stabilize my ram. Whatever I did, sooner or later, eventually, it failed AIDA stresstest. And I've only tested system memory - no CPU,FPU or cache stresstest.

First I tried it with both RAM and CPU overclocked.
Then I returned the CPU to stock settings, reset everything, leaving only RAM.
Tried 1.35v, 1.4v, 1.45v, 1.5v respectively, each time I've raised to 1.10v, 1.15V, 1.20v SA/IO
Then I've set SA and IO to default 0.95 and 1.05v, and tried all over again with vRAM.

Whatever voltages for SA, IO and vCore I use (aswell as CPU clock), I have it like this:
1.35v - unstable
1.4v - unstable
1.45v - unstable
1.5v - awfully unstable, crashed in 3 minutes.

Plus, I've managed to boot with 3466MHz at CL14 with 1.45V vRAM, but still not stable in AIDA.

Nothing worked out. At all. AIDA always gives out an hardware error.

[dmt_taran]

BTW, I've never mentioned exactly what ram do I have.
https://www.gskill.com/en/product/f4-3000c14d-32gtzr

And that fact, that I can't achieve literally anything at all, frutrates me even more.

[NemesisChild]

I personally have never used AIDA64. Have you tried RealBench?

[dmt_taran]

NemesisChild wrote:
I personally have never used AIDA64. Have you tried RealBench?

No, only aida and testmem.
However, PC is not stable even on daily basis - games, chrome, apps keep crashing, maybe bot instantly but in couple of hours, but it's still not stable

[lassek]

I have now found the ultimate solution! Im running 3333 Mhz @ 14-14-14-34 1.4v

VCCIO and VCCSA is 1.2v

This set of secondary timings are tight and gives overall amazing performance and ultra low latency combined with the primary.

This gives transfer rates matching 3500/3600 Mhz but up to 20% better latency! Compared to CL16!, Incredible 45ns in my case.

I have tested this VERY thoroughly and they are ROCK stable settings, also my CPU is a bad bin (SP 63) with a weak IMC, so im trying to say everybody should be able to run these settings at least with this RAM kit! .... My kit was OEM 16-16-16-36 3600 Mhz G Skill.

This defiantly seems like the best overall solution for stability and performance.

UPDATED: I updated to secondary timings a notch more tight to perfectly match SPD CL14 @ 1018 Mhz from the table.. So its pretty impressive these tight timings actually works on my 1666 Mhz setting (3333 Mhz)

The full timing set: 14-14-14-34 2N - RFC1-357 RFC2-265 RFC4-163 RRDS-4 RRDL-6 FAW-22 @ 3333 Mhz @ 1.40v

[lassek]

UPDATED on top

[BigJohnny]

overclocking the ram gets tricky. You will never get the best results with XMP enabled. They all react differently.
I generally leave my ram in auto and OC CPU first. Then go for the ram once thats stable. Remember there are two parts to the equation. 4000 at CL19 wont give you anymore bandwidth than 3600 CL16, the latter is actually a little better. Best Bdie kit out there is 3200 CL14.
To get the best ram OC you will have to go digging in the tertiary timings as well. Its all trial and error and there are no magic numbers. Every kit is different even those with the same sku.
There's a lot of guides out on YouTube to get you started.