RX 5700 XT - memory clock spread spectrum?

[RPX100]

I am wondering how the RX 5700 XT memory clock is controlled,
and if there is such a thing as "GPU memory spread spectrum"?

Adrenalin 20.11.2 (nov 2020) changed the memory clock behavior,
or at least changed how the value is displayed to the user (on a driver level).

- Stock RX 5700 XT memory clock is 1750 MHz (GDDR6 Micron)
- GPU-Z reports 1750 MHz default memory clock (on first tab)
- but on the sensors tab the memory clock fluctuates from 1742 - 1754 MHz (under load)
- any driver before 20.11.2 was always reporting 1750 MHz stable, no fluctuation
- installing 20.8.3 for example will still show 1750 MHz stable (even today).

So to get to my question:
Could this be a driver enforced "spread spectrum"?
(or has it always been running like this and they changed the way it is displayed?)

 

[eidairaman1]

Id say change way its reported, gpus rev up and down depending on what fps there are to save power. I personally dislike it myself and if a bios mod prevented a gpu from reving up and down I would fo it.

 

[RPX100]

Hm, oh well... I was hoping for a bit more response/discussion.

You might indeed be right, that they only changed the way it is reported,
but it still feels strange to see memory clocks fluctuate like that.
I was under the impression that memory becomes more unstable with fluctuation.

In general I am not totally against power saving features - rather like them actually.
It does become annoying when the GPU downclocks during gaming tho.

 

[RJARRRPCGP]

I get VRAM frequency readings like that, too, on my RX 5600 XT.

 

[RPX100]

I have been scrolling through some reddit posts, that I found via google while searching
for some more feedback and maybe even some insights regarding this issue.

Some people believe this does indeed change the actual memory frequency,
in an attempt to prevent the black screen issues, that a lot of the 5000 series cards seem to have (had).

And these posts also confirm that the memory clock fluctuates for other 5000 series cards,
so it is indeed not just limited to the 5700 (XT) cards.

I still do not have proof for it being real clock spread or just different way to display the value.
After all, it could have been fluctuating all the time, but AMD was displaying the adjusted value before.

---
side note: I might install 20.8.3 again and see what registry values are different there.

 

[RPX100]

I had a look at the registry key differences from 20.8.3 to 21.9.1 today.
Sadly, there is nothing related to the memory clock behavior in there.

I also did some more searching for information about this topic,
but all there is to find seems to be people complaining about the clock fluctuation.

---
... and I can also confirm that the 2 driver background services do not change this either.
(AMD External Events Utility and AMD Crash Defender Service)

 

[Athlonite]

in the performance-tuning page of Radeon settings under where it says memory tuning there's a drop down for Memory timings you get a choice of Default or Fast timing there are also settings for min/max speeds did you try setting those the same so min = 1750 & Max = 1750

 

[eidairaman1]

in the performance-tuning page of Radeon settings under where it says memory tuning there's a drop down for Memory timings you get a choice of Default or Fast timing there are also settings for min/max speeds did you try setting those the same so min = 1750 & Max = 1750

View attachment 219309

Too bad there isn't fine tuning to relax or tighten them further. Does Afterburner or Trixx do that?

 

[RPX100]

I have not used Radeon Software since Jan 2021, because it was causing too much problems for me.
But I have never seen those sliders being available on my own RX 5700 XT.
The only thing available on RX 5700 XT was MHz slider for Memory clock - nothing about timings.
-> but I did not look into Radeon Software since Jan 2021 ... so it could have been changed by now.

Is your screenshot from current 20.9.1 (or newer) and RX 5000 series, or is this RX 6000 series screenshot?

Does Afterburner or Trixx do that?

Afterburner does not have an option to change memory timings, only memory clock (MHz slider).

 

[eidairaman1]

I have not used Radeon Software since Jan 2021, because it was causing too much problems for me.
But I have never seen those sliders being available on my own RX 5700 XT.
The only thing available on RX 5700 XT was MHz slider for Memory clock - nothing about timings.
-> but I did not look into Radeon Software since Jan 2021 ... so it could have been changed by now.

Is your screenshot from current 20.9.1 (or newer) and RX 5000 series, or is this RX 6000 series screenshot?


Afterburner does not have an option to change memory timings, only memory clock (MHz slider).

Try advanced under AB(gear icon)

 

[RPX100]

There is no other memory option available in Afterburner.

 

[AusWolf]

If I remember right with my 5700 XT, my memory clocks fluctuated too, though only a couple MHz. If performance is OK, I'd say, don't worry about it.

 

[RPX100]

@Athlonite Just looked at the screenshot again - that is indeed not an 5000 series card.
But it looks like the 6000 series has the same memory fluctuation (1986 MHz instead of 2000).

edit: Oh and that memory timing setting is for the memory straps/timings for the selected frequency.
So it changes memory timings (latency) rather than the clocks.

 

[Athlonite]

@Athlonite Just looked at the screenshot again - that is indeed not an 5000 series card.
But it looks like the 6000 series has the same memory fluctuation (1986 MHz instead of 2000).

edit: Oh and that memory timing setting is for the memory straps/timings for the selected frequency.
So it changes memory timings (latency) rather than the clocks.

Yes it is I had it on my RX5700 aswell what driver are you running I think this showed up around the 20.9.xx or later driver also in that same area you can select a min/max setting for ram clocks I don't bother because it doesn't really affect performance

 

[RPX100]

what driver are you running

I have been using 20.8.3 for a long time and tested 20.11.2, 20.12.1, 21.1.1 when they were new.
Currently using 21.9.1 because it added smart access memory support to the 5000 series.

But I did not see that memory timing control in Radeon Software, back when I was using it.
For my card it was only displaying the memory clock slider, nothing else.
As I said tho: Have not been using Radeon Software since January, because of crashes/problems with it.

But this timing control does not have influence on the memory clock itself, only the timings for that selected clock.