Ryzen speedstepping, how does it work?

[idiocracy]

My cpu looks like this all the time.

 

 

 

Now the cores are constantly switching, but at any given point at least 1 core are always at +4ghz, but only for a very short time as they're constantly switching. This is if the machine is idle and has less than 4% load.

I havn't tried oc yet because it just seemed unnecessary at this point in time. The only thing i changed in the bios was memory xmp profile.

The latest AMD drivers are installed, and so is the latest bios. What i am expecting to see is speedstepping down to ~.8/1.5ghz.

But what am i supposed to see?

How does ryzen speedstepping work?

 

The bios looks like this default.

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Options.

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When AMD is set. And when set and saved the result in windows looks the same as above.

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[Guest]

Is "amd cool and quiet" enabled in bios? Also dont expect the cpu to jump down to 0.8ghz, there just is no point. It wont save you much power, it is easier to keep the cpu in 3-4ghz range. Also there is quaranteed that some background task is using the cpu, that could also be the case.

[idiocracy]

1 minute ago, Some Random Member said:

Is "amd cool and quiet" enabled in bios? Also dont expect the cpu to jump down to 0.8ghz, there just is no point. It wont save you much power, it is easier to keep the cpu in 3-4ghz range. Also there is quaranteed that some background task is using the cpu, that could also be the case.

Yes it is enabled. Now, i can understand it won't step down to .8ghz, but i would've expected ~1.5ghz to be an idle point, not idling at 2.9ghz for .5 sec, jump to +4ghz for .5 sec, jump to 2.9ghz ag.... Let me just show you instead.

Spoiler

 

 

I have browser open, a mail client and hwinfo. Background programs are dropbox, CAM, audio, steam, afterburner, networx, daemon tools, teamviewer and virus.

Total cpu utilization is ~2%

But i don't know what the normal behaviour is.

[Guest]

1 hour ago, idiocracy said:

I have browser open, a mail client and hwinfo. Background programs are teamviewer and virus.

 

I dont know why you would have a virus as a background program, but maybe it's just me. Usually people try to get rid of viruses. /s

 

Anyways that is totally normal behaviour. I have a previous gen ryzen, the r7 1700, and it idles at about 2.5ghz, but also the cores jump around a lot. You have a 2. gen ryzen, so 1ghz higher.

 If you disable core performance boost the clock speed doesn't jump around as much, but you lose a lot of single thread performace, so i would have that enabled.

[idiocracy]

20 minutes ago, Some Random Member said:

I dont know why you would have a virus as a background program, but maybe it's just me. Usually people try to get rid of viruses. /s

 

Anyways that is totally normal behaviour. I have a previous gen ryzen, the r7 1700, and it idles at about 2.5ghz, but also the cores jump around a lot. You have a 2. gen ryzen, so 1ghz higher.

 If you disable core performance boost the clock speed doesn't jump around as much, but you lose a lot of single thread performace, so i would have that enabled.

Well, if it's normal i'll just leave it. Was just wondering because it's quite a different behaviour than what i've been used too. I just thought it seemed extreme that it jumps around like that almost 3 times a sec, seemed a bit overkill for a system that wasn't really doing anything.

 

And virus aka antivirus was windows defender.

 

Edit:

Hold on.

The minimum cpu state in the AMD power plan is 90%. Now i've read that is because windows is too slow to change p-state, and to eliminate windows the min cpu state is set to 90% so that it does not interfer with sensemi. But i just tried changing it to 60% instead.

Because i read another place that min cpu state should just be set to minimum 20% to avoid the issue. But now at 50% it speedsteps to 2195mhz, and does so more evenly over all cores.

I did test 20% but it's the same 20%-60%

Edit: Oh yeah, i can already see it on the idle temps.

[Guest]

12 hours ago, idiocracy said:

 

The minimum cpu state in the AMD power plan is 90%. Now i've read that is because windows is too slow to change p-state, and to eliminate windows the min cpu state is set to 90% so that it does not interfer with sensemi. But i just tried changing it to 60% instead.

Because i read another place that min cpu state should just be set to minimum 20% to avoid the issue. But now at 50% it speedsteps to 2195mhz, and does so more evenly over all cores.

I did test 20% but it's the same 20%-60%

Edit: Oh yeah, i can already see it on the idle temps.

What can you see in idle temps? Also use cpuid HWmonitor, it shows how many watts your cpu is using.

Anyways im interested, because i have just left it as it is, because at idle cpu power usage is low enough.

[idiocracy]

2 hours ago, Some Random Member said:

What can you see in idle temps? Also use cpuid HWmonitor, it shows how many watts your cpu is using.

Anyways im interested, because i have just left it as it is, because at idle cpu power usage is low enough.

I'm using hwinfo, and the lowest watt usage is 19.461w. More realistically it hovers around 20.3w. Temp dropped ~5c

 

This is what i've learned so far, adding this for future reference.

1. AMD power profile has minimum cpu state set to 90% because windows might try to take control of the p-states which interferes with sensemi. Windows is too slow, and sensemi does a better job of controlling p-states.

To avoid that they set the minimum cpu state high. But it doesn't need to be 90%, 60% will accomplish the same(as far as i know), but allow sensemi to go a bit lower than 2995mhz.

 

2. AMD adjusts core freq ~3 times per sec. It will lower it's clocks, but sensemi adjusts so fast that just the slightest input from the user will increase it's clocks. So when you're looking the clocks might appear higher than they actually are.

One reason is that windows task manager shows you the average clocks. So one core might be 4.1ghz and the 5 others 2.1ghz.

 

3. After installing AMD drivers, AMD power profile is selected by default, it should be left at that. However you might change "pcie power savings" to none, and minimum cpu state to 60%.

 

In the future i'd wish to see updates that allow the cpu to clock even lower. 1.3 to 1.7ghz should be just fine for surfing the interwebs and watching cats on youtube.