Question basic question regarding DDR5 RAM (frequency and timings)

[Turbonium]

Say you're running a Raptor Lake system, and you have a set of paired RAM DDR5 sticks that are supposed to be able to run at a certain set of low timings at a given speed. In this case:

DDR5-6200
32-38-38-80

You manually set the DRAM frequency in UEFI BIOS to 5600 (up from the 4800 it defaulted to). Just ignore the tested XMP speed of 6200 for the sake of this question.

You then do some basic testing (i.e. gaming) and things seem to be running just fine. No stability issues whatsoever (not stress tested by any means though, but I doubt it's really necessary).

CPU-Z reports the following current (default) timings when DRAM is manually set to 5600:

48-47-47-89
(assuming I'm reading it right)

I assume these are slow/lazy values, especially considering the memory can do much tighter timings at a faster speed (6200 and 32-38-38-80 as mentioned).

Would I be safe to just tune the timings straight away to 32-38-38-80 while running at 5600? Again, it's currently at 5600, not the 6200 XMP the memory was rated at.

 

[Turbonium]

Just tried to go ahead and do just that, and I can't seem to change any of the timing values (despite the plethora of details in BIOS).

Mobo: Asus Pro B760M-CT with latest BIOS.

"DRAM Timing Control" leads to the second screen, but everything is fixed to Auto and I can't seem to change it (it gives me no options for other values).

Changing "Ai Overclock Tuner" has 3 options: Auto, XMP I, XMP II

(It has no "manual" option.)

Any ideas on what I'm doing wrong? I'm really hoping this isn't a limitation of my motherboard.

 

[In2Photos]

I believe Intel B series motherboards have limited overclocking abilities. Manual RAM timings are likely not available.

 

[Turbonium]

I believe Intel B series motherboards have limited overclocking abilities. Manual RAM timings are likely not available.

Learning experience for sure if true.

Can anyone confirm this?

Also: does tinkering with timings even count as overclocking? I wasn't aware it did.

(The mobo's technical specifications page mentions OCing of memory to be a thing, so I don't see why timings wouldn't be modifiable.)

 

[tcsenter]

Have you tried the ASUS apps to see if offered through software? Probably not going to get overclocking with the B family chips but should have some timings adjustment.

 

[Turbonium]

Have you tried the ASUS apps to see if offered through software? Probably not going to get overclocking with the B family chips but should have some timings adjustment.

What do you mean offered through software? You mean mobo-specific programs? Honestly, I doubt they even exist for this mobo in that sense, as it's a corporate/business-tier motherboard. Even so, I don't see why timing adjustment shouldn't be available in the BIOS as-is (I totally get it if I can't adjust voltages manually though).

 

[Turbonium]

I thought of a "workaround" that really shouldn't have to happen.

Get DDR5 -5600 RAM with a built-in XMP profile (CL 40 or better), and use those sticks instead of these DDR5-6200 sticks which I'm trying to run at 5600.

I mean, I'd rather just run these sticks at tight timings, if this board would only let me. I know it's a corporate-grade board but, wtf. It lets me set XMP timings at 6200, but not the same (or any custom) timings at 5600, simply because it would be a "manual" calibration done by me. Seems so silly.

CPU is a K series, if it matters (13600KF).

 

[Turbonium]

So apparently, I was doing it wrong (had to chat with Asus support to figure it out too, lol).

Anyway, which of the values I'm looking at are the ones I'm supposed to change?

(I want to set it to what would be considered:
32-38-38-80)

Would that be:

DRAM CAS# Latency: 32
DRAM RAS# to CAS# Delay Read: 38
DRAM RAS# to CAS# Delay Write: 38
DRAM RAS# PRE Time: 38
DRAM RAS# ACT Time: 80

?

Totally don't know what I'm doing here.

 

[Turbonium]

Here, how's this look? And is my Bank Cycle Time (tRC) too slow?:

-

 

[Hotrod2go]

Here, how's this look? And is my Bank Cycle Time (tRC) too slow?:

View attachment 84989

Can you show the SPD tab please? That board you linked too looks too plain to have any enthusiasts tweaking options in it. I'd be surprised if manual setting of RAM timings is doable. However the only way to know if the tRC is too high is to check the XMP profile in the SPD tab.

 

[Turbonium]

Can you show the SPD tab please? That board you linked too looks too plain to have any enthusiasts tweaking options in it. I'd be surprised if manual setting of RAM timings is doable. However the only way to know if the tRC is too high is to check the XMP profile in the SPD tab.

Iirc, the tRC is identical to (or slightly less than) the JEDEC/XMP profiles on the SPD tab.

The timings are 100% modifiable on this board, as are the voltages (the timings you're seeing were set manually by me; same with the current voltage of 1.25 V).

I might post a screenshot of the SPD tab later today.

 

[Turbonium]

-

Again, running the sticks with 1.250 V (5600; 32-38-38-80), with a tRC of 118 at 2T.

The SPD data above tells me my tRC value is fine, but I thought I'd post it anyway.

Extra data:

-

 

[igor_kavinski]

I would be interested in JEDEC #5.


It should give you lower latency and with hyperthreading turned off, your CPU will find the bandwidth to be sufficient. Try it. It might be to your liking.

 

[Turbonium]

I would be interested in JEDEC #5.

View attachment 85021
It should give you lower latency and with hyperthreading turned off, your CPU will find the bandwidth to be sufficient. Try it. It might be to your liking.

Wait, what?

But I'm already running fine at higher frequency, and lower timings, just fine. See above.

I'm not sure I understand.

 

[igor_kavinski]

Wait, what?

But I'm already running fine at higher frequency, and lower timings, just fine.

In your previous posts in other threads, you mentioned your preference for lower DIMM voltage.

JEDEC #5 settings will ensure that you have a completely stable system. The bandwidth will be reduced so you can offset the need for that by disabling HT. Fewer active threads will reduce your CPU temps and power usage, allow those threads access to double the cache and get higher ST frequency boosts. My friend runs his i5-12400 without HT and he's happy with the performance.

 

[Turbonium]

In your previous posts in other threads, you mentioned your preference for lower DIMM voltage.

JEDEC #5 settings will ensure that you have a completely stable system. The bandwidth will be reduced so you can offset the need for that by disabling HT. Fewer active threads will reduce your CPU temps and power usage, allow those threads access to double the cache and get higher ST frequency boosts. My friend runs his i5-12400 without HT and he's happy with the performance.

I was saying I don't know if higher voltage is bad practice or will lower the lifespan of any components, etc. If my running 1.250 V is well within spec and "normal" for a DDR5-5600, I don't mind it at all.

 

[Hotrod2go]

Iirc, the tRC is identical to (or slightly less than) the JEDEC/XMP profiles on the SPD tab.

The timings are 100% modifiable on this board, as are the voltages (the timings you're seeing were set manually by me; same with the current voltage of 1.25 V).

I might post a screenshot of the SPD tab later today.

Thanks for uploading that screenshot for SPD details. The 5600MT/S you have running, is that stable? It's a setting that not's native to your particular set of RAM. Your running the tRC of your XMP profile but with 1.25v - & that's relevant to the rest of your major timings too. Be sure to stress test this config before doing anything important in Windows, otherwise you'll corrupt system files & it can happen without obvious program lock ups, etc... among other tell tale signs of instability even before you login. Run MT86 as a bare absolute minimum before venturing into the Windows environment. Then I would run Windows memory diagnostics app & depending on the outcome, take the testing further from there...

 

[Turbonium]

Thanks for uploading that screenshot for SPD details. The 5600MT/S you have running, is that stable? It's a setting that not's native to your particular set of RAM. Your running the tRC of your XMP profile but with 1.25v - & that's relevant to the rest of your major timings too. Be sure to stress test this config before doing anything important in Windows, otherwise you'll corrupt system files & it can happen without obvious program lock ups, etc... among other tell tale signs of instability even before you login. Run MT86 as a bare absolute minimum before venturing into the Windows environment. Then I would run Windows memory diagnostics app & depending on the outcome, take the testing further from there...

Seems stable based on regular usage and gaming, yeah.

I'll try an actual memory test soon.

 

[Hotrod2go]

Seems stable based on regular usage and gaming, yeah.

I'll try an actual memory test soon.

Seems stable & actually stable are 2 different things.