Manual Tuning vs XMP/EXPO

Grumbledook · 26 Oct 2023 at 19:17

How likely is it you can get more speed and or CAS timing improvements manually tuning compared tho the overclock profiles on a RAM set?

Looking at buying some 6000 MT/s CL30 memory for my new AM5 build and wondering how likely it is I could push the speed or latency beyond those numbers?

Jamin280672 · 26 Oct 2023 at 20:25

Grumbledook said:
How likely is it you can get more speed and or CAS timing improvements manually tuning compared tho the overclock profiles on a RAM set?

Looking at buying some 6000 MT/s CL30 memory for my new AM5 build and wondering how likely it is I could push the speed or latency beyond those numbers?

There's a lot of voltages to consider, and how far you are willing to push them, but 6000mhz CL30 will most likely be hynix A die which is very overclockable, or keep it at 6000mhz and dial down the timings, most are getting them down to CL28, others are CL26 but depends on the CPUs IMC.

You've got the VDD voltage which is ram voltage
VDDIO memory controller which you can now also adjust the timings for known in the bios as DDR5 Nitro Mode.
SOC voltage which is UNCore voltage
VDDQ which is data channel sent back to the memory controller / IO die. (set this the same as VDDIO)

Mine is VDD 1.45v
VDDIO and VDDQ 1.375v
SOC is 1.25v

Grumbledook · 26 Oct 2023 at 20:31

Thanks Jamin, that's exactly the sort of info that I was after.

Build might not get completed until after Black Friday / Cyber Monday. I'll try and report back with what I buy and the results of any tweaking I do.

Rroff · 26 Oct 2023 at 20:36

In my brief experience, and from what others have said so far, once you get to 6000MHz CL30 you are into diminishing returns, dialling in the settings you can get a little extra from sub-timing tweaks but not really worth it over just whacking in XMP - won't get as much extra as you would from paying the additional ~£20 for some 6400MHz modules but that won't be hugely noticeable either.

dave28 · 26 Oct 2023 at 20:42

If you know what you are doing then manual is better i think, the XMP profiles are designed to work in a broad range of systems.
But with manual you are doing it for your system specifically.

Jamin280672 · 26 Oct 2023 at 20:50

Grumbledook said:
Thanks Jamin, that's exactly the sort of info that I was after.

Build might not get completed until after Black Friday / Cyber Monday. I'll try and report back with what I buy and the results of any tweaking I do.

Have a look here, some very helpful info and guys over here: https://www.overclock.net/threads/a...aily-memory-stability-thread.1800926/page-489

This is where im at, bear in mind 6000mhz CL30 was giving me about 61ns latency, and nothing above 90MB/s read / write copy https://forums.overclockers.co.uk/t...-how-to-tune-overclock.18979304/post-36743879

Grumbledook · 27 Oct 2023 at 19:46

Thanks, I'll do some further reading.

Found good deals on the remaining parts today that I don't think Black Friday will beat so looks like the build might happen next week.

I've ordered 64GB G.Skill
F5-6000J3040G32GX2-TZ5NR
Trident Z5 Neo RGB DDR5-6000 CL30-40-40-96

JollyJamma · 28 Oct 2023 at 10:27

Grumbledook said:
How likely is it you can get more speed and or CAS timing improvements manually tuning compared tho the overclock profiles on a RAM set?

Looking at buying some 6000 MT/s CL30 memory for my new AM5 build and wondering how likely it is I could push the speed or latency beyond those numbers?

Here, watch this

2x16GB DDR5-6200 CL26! with Ryzen

Text version: https://www.patreon.com/posts/80045691EDIT: It has a occured to me that with DDR5 memory VDD voltage should be pretty much completely internal ...

youtu.be

Jamin280672 · 28 Oct 2023 at 19:09

This is what im trying at the moment, this is 1.5v VDD, 1.25v VDDIO and 1.4v VDDQ, max temp is 55.6oC on each stick at the moment, so far ive got through 10 cycles of TM5 1usmus_v3 test, not sure theres much more I can tighten up here, 6400mhz at CL30 with very tightened sub timings.

Grumbledook · 28 Oct 2023 at 22:22

JollyJamma said:
Here, watch this

2x16GB DDR5-6200 CL26! with Ryzen

Text version: https://www.patreon.com/posts/80045691EDIT: It has a occured to me that with DDR5 memory VDD voltage should be pretty much completely internal ...

youtu.be

1.6v seems rather high, wasn't there a problem with voltages on AM5?

Tetras · 28 Oct 2023 at 22:25

Grumbledook said:
1.6v seems rather high, wasn't there a problem with voltages on AM5?

It is the soc you definitely don't want @ 1.6v, but this is buildzoid, he only keeps anything until he breaks it or it is obsolete

Grumbledook · 28 Oct 2023 at 22:27

Tetras said:
It is the soc you definitely don't want @ 1.6v, but this is buildzoid, he only keeps anything until he breaks it or it is obsolete

Fair enough

I tend to keep kit for up to 5 years.

Might just have a play around if I find the time anyway to see what I can push it to.

Jamin280672 · 28 Oct 2023 at 22:47

Grumbledook said:
Fair enough I tend to keep kit for up to 5 years.

Might just have a play around if I find the time anyway to see what I can push it to.

He was saying monitor temps, 1.6v VDD needs a fan over the ram sticks to keep them around 50oC, currently im running 1.5v VDD without any cooling and hitting 55oC, no errors so far though so I guess this is OK, I wouldnt want to put anymore voltage through them without a fan on them though, bear in mind, im not always going to be running intensive tests on my ram, so they will probably never hit 55oC again.

Something I didnt know is the DDR5 IO PMIC voltage (VDDQ) is meant to be kept at the same voltage as the VDD voltage or there abouts, otherwise he was saying it can damage the sticks, he said 100mv here and there shouldnt matter though, so ive set mine to 1.4v, ive dropped the VDDIO (mem controller voltage) to 1.25v which has surprised me.

I couldnt tighten timings anymore than above, anything tighter and im getting errors early on, this could be the VDDIO voltage being too low though, so I may have a play with that again yet.

Grumbledook · 29 Oct 2023 at 09:14

Useful tidbits, thank you.

What app(s) are you using for your intensive tests?

Jamin280672 · 29 Oct 2023 at 12:06

Grumbledook said:
Useful tidbits, thank you.

What app(s) are you using for your intensive tests?

I start with TM5 using 1usmus_v3 profile, for a quick 1 and a half hour test (25 passes)
then when im happy with speed and timings and passing TM5 I move onto Y-Cruncher 1-7-0, 3 to 4 hours, but not until im finished tweaking.
finally Memtest Pro for longer testing (usually overnight) approx 2000%

HWInfo for monitoring RAM temps etc.

Jamin280672 · 29 Oct 2023 at 18:56

To finish a day of testing off, this was the best I could do with 6400mhz, ignore the 63.8oC thats a bork reading, but its well known for A die PMIC to do this, 54oC is closer to the truth, im just running a few full passes of Y-Cruncher and then i'll let memtest pro run overnight, anything tighter on timings either had a negative effect or gave errors.

Ended up with
1.50v VDD
1.45v VDDQ
1.25v SOC
1.25v VDDIO

Grumbledook · 30 Oct 2023 at 13:40

All the parts have arrived but I'm busy tonight. Probably not going to be able to build until Wednesday evening, or on Thursday as I'm off work.

Can confirm that the G.Skill 64GB is A-die. (The A at the end of the Code number, or M if it's M-die). Fresh off the assembly line given it was manufactured on the 19th October!