Cant go past 3866 ram on 8700K?

[roidroo]

3200 cl14 16gb g skill ram kit
Asrock extreme4 Z370 mobo
8700K 4.8ghz no avx

When I go above 3866 at 19-21-21-42 my write and copy drop to 40000 scores, latency goes to almost 50ns. My guess is it gets unstable at higher frequencies. Any ideas how I can eek more oc out of this?

What am I limited by? My IMC? Board is rated for at least 4133 on their website

OC pic and results - https://ibb.co/q0YPBHB

 

[dejo]

your IMC can limit you as well as the ram itself.
Are you just setting the base timings of 19-21-21-42 and leaving the rest at auto? As some of the timings past the initial can hamper you as freq go up.
I would think that you could attempt something like 18-18-18-38 for 3800 with auto past those and potentially boot

 

[roidroo]

I went as far as 16-16-16-35 4133 with pretty much same secondary and tertiary timings as in the pic linked
Higher freq no matter what I do drops my write and copy scores to sub 45000 in aida. More voltage and looser timings dont fix it
I was getting 61000 read 42000 write 45000 copy from a baseline of 54000 read 40000 write 40000 copy 19-26-26-46 4133
The wall happens at 3866. Even 3900 results in this drop off. Same with 4000. I havent bothered with anything higher than 4133 for testing. Doubtful that 4266 would somehow be golden
I can't hit CL14 at 3866 or 3800. Only at 3733 and 3700 which results in bandwidth lost.
Wanted to push harder but I'm lost

 

[dejo]

if you have cpuz installed look at the memory tab and make sure you are in dual channel mode. that can make a large difference in aida64 speeds. you may have a stick of ram failing as well. could try and boot with a single stick to see if it boots better timings. if issues try the other stick as a single stick

 

[magellan]

I have an asrock z390 Taichi with a 9700k. Getting anywhere above 3900Mhz. looks to be impossible, but maybe with higher VCCIO and VCCSA it might be possible, but then the CPU heat output becomes problematic.

 

[roidroo]

if you have cpuz installed look at the memory tab and make sure you are in dual channel mode. that can make a large difference in aida64 speeds. you may have a stick of ram failing as well. could try and boot with a single stick to see if it boots better timings. if issues try the other stick as a single stick

Just tried booting at 4133CL19 and it said dual channel in cpuz. Aida scores are ~52-53000, >40000, >40000

I have an asrock z390 Taichi with a 9700k. Getting anywhere above 3900Mhz. looks to be impossible, but maybe with higher VCCIO and VCCSA it might be possible, but then the CPU heat output becomes problematic.

I'm not sure it's a voltage issue. 3866 runs fine with 1.2 SA VCCIO 1.45DIMM voltage, I even plan to undervolt the vccio and dimm once I've gamed on it and seen it stable. 1.5V DIMM, 1.3VCCIO & 1.30SA make no difference to my 4133 or 4000 attempts even though they boot fine at 1.5V, 1.25, 1.25V

 

[magellan]

Just tried booting at 4133CL19 and it said dual channel in cpuz. Aida scores are ~52-53000, >40000, >40000

I'm not sure it's a voltage issue. 3866 runs fine with 1.2 SA VCCIO 1.45DIMM voltage, I even plan to undervolt the vccio and dimm once I've gamed on it and seen it stable. 1.5V DIMM, 1.3VCCIO & 1.30SA make no difference to my 4133 or 4000 attempts even though they boot fine at 1.5V, 1.25, 1.25V

What are the settings for your RTL and IO-L in BIOS? It could be you're using single-rank DIMM's since you only have 16GiB (2x8GiB), I think I have dual rank DIMM's because I have 32 GiB (2x16GiB) which makes it easier on the IMC.

The highest I got was 4111 Mhz with my G-Skill 2x16GiB Ripjaws-V kit, but after a cold boot it could never train to that speed again and now not even 4000Mhz is stable anymore

 

[roidroo]

What are the settings for your RTL and IO-L in BIOS? It could be you're using single-rank DIMM's since you only have 16GiB (2x8GiB), I think I have dual rank DIMM's because I have 32 GiB (2x16GiB) which makes it easier on the IMC.

The highest I got was 4111 Mhz with my G-Skill 2x16GiB Ripjaws-V kit, but after a cold boot it could never train to that speed again and now not even 4000Mhz is stable anymore

Not sure. didnt touch anything past tertiary timings. Pretty sure they're single ranked because they're b-die. Not too sure