F4-3866C18Q-32GTZR on ASUS Maximus XI Hero Overclocking

[cniedzi]

Hi,

I've noticed strange issue when I've tried to overclocked my F4-3866C18Q-32GTZR on ASUS Maximus XI Hero.

I can get max 3900MHz 17-17-17-36 2T @VCCIO 1.10V, VCCSA 1.15V in DRAM Timmings Mode 2 (1st screen). If I go higher Write to memory bandwith drops to ca. 30000MB/s (Copy too) - 2nd screen . I can't get higher bandwith in Mode 2.
In Mode 1 I'm able to get 4133MHz, memory bandwith looks pretty well, Karhu RAM Test 12000% passed, but WinRAR extraction of big (>10GB) rar file fails (CRC errors)

Is there any explanation of above issue?

regards

[GSKILL TECH]

What BIOS version are you using?

Have you tried boosting DRAM Voltage and/or SA Voltage for DDR4-4133?

[cniedzi]

Bios 905 and 1001. Increasing voltages does not help.

[GSKILL TECH]

Check sub timings to see if they are correct. May need to manually input them or adjust in case they are changing when set to a value between 3900-4133 as you mentioned.

[cniedzi]

What timings should I try @4133?

[GSKILL TECH]

See if the sub timings are the same when running 3866 and 4133. There's no reason performance drops when running at a higher frequency unless something else was not configured properly.

[cniedzi]

These are my timings for 3900MHz (1st row) and 4000MHz (2nd row). Should I change something for 4000MHz to avoid performance drops?

[cniedzi]

Thx. Success !!!

I've copied 3rd timings from 3900MHz profile and I've got 4133MHz @18-18-18-36-2T (DRAM Voltage 1.40V, VCCIO 1.15V, VCCSA 1.15V) without performance drops.

Are these voltages safe for my F4-3866C18Q-32GTZR?

[GSKILL TECH]

Very good actually, looks like you did a great job.

Enjoy