Intel Extreme Tuning Utility changes its default values

[APart1]

I have a laptop with an i7-6560U CPU. I'm having a really annoying problem with Intel XTU when trying to undervolt the CPU. It works well at first, and I'm getting a 20% performance boost when the CPU is TDP limited.

Default: 0.00 mV, Active: -93.75 mV, voltage is lowered by ~0.09 V.

But then, randomly, after a sleep cycle (close & open the lid), the default voltage is changed to match the active one and XTU interprets this as "I don't have to do anything".

Default: -93.75 mV, Active: -93.75 mV (http://ajpanton.se/XTU.png Screenshot), voltage goes back to normal.

As there is no way to change the default manually, I have to change the voltage by just a tiny bit, and it works again.

Default: -93.75 mV, Active: -92.77 mV, voltage is lowered by ~0.09 V.

Until after a few days, the default matches my active value again:

Default: -92.77 mV, Active: -92.77 mV, voltage goes back to normal.

I have to constantly battle this by changing the voltage offset back and forth:

Default: -92.77 mV, Active: -93.75 mV, voltage is lowered by ~0.09 V.

[idata]

I'm not sure how to solve the wake from Sleep issue it seems IXTU is having with your laptop. You might want to include the version of IXTU you are using in your post, as I'm sure Intel Support will ask you about that.

I have some questions about your situation:

You said the loss of your voltage settings occurs "... randomly, after a sleep cycle...", and then later you said, "... Until after a few days, the default matches my active value again".

I'm wondering if the case where you lose your voltage settings is caused by the PC coming out of Hibernation, rather than just Sleep.

On my desktop PC (Z170 board, Skylake processor, IXTU version 6.0.2.8) after applying changes via IXTU, and exiting IXTU manually (which means IXTU does NOT auto-start after any of the following situations), and restarting the PC (not a shutdown), the changes I made in IXTU are not lost. I can shutdown the PC, but not remove power (PSU not turned off), and the IXTU settings are not lost. At no time after the restart of the PC, or before I shut it down, did I run IXTU. I ran it once to apply my settings, and then manually exited IXTU.

My point here is IXTU will only apply a change in settings when we manually tell it to do so. A wake from Sleep or Hibernate situation does not cause our settings to be applied, nor does a cold start after a shutdown. So your idea that IXTU decides "I don't have to do anything", is not how it seems to work. Given that my PC retains the changes I made, since I did not run it at all after applying my changes once, IXTU does not need to run and apply any changes to maintain them, and therefore should not be expected to be applying any changes. If and when you do lose your changes in IXTU, the fact that you don't see the change to the default voltage makes no difference. IXTU is not even checking that any changes it made have been maintained. That is, if it can really know what the last change we made is.

Since you say the loss of your voltage setting seems to be random (random problems are the most difficult to diagnose), I suggest you pay close attention to your interaction with the PC, in order to try to discover if there is anything that happened that might cause the loss of your applied IXTU voltage setting.

You said you get a 20% performance boost when the TDP is limited. How are you measuring or determining this 20% boost in performance?

I have a suggestion to help you restore your voltage setting when you lose it. Have you tried saving your setting(s) in an IXTU profile? Profiles is an option on the left side of the IXTU screen. First manually set the voltage value you use, and Apply it. Then go to the Profiles screen, you should see your setting(s) on the right side of the screen, and Save should be highlighted below the settings. Click on Save and give the profile a name.

To load the Profile, go to the Profiles screen, and click on the profile name. Above the profile names, find the Show Values button, and click it. You'll see your setting(s) populated on the right side of the screen. Then click the highlighted Apply button below the settings display, which should apply the setting(s).

[APart1]

I don't think I've ever hibernated with this laptop yet, so no, that's not it. It just happens after a random number of sleep cycles, which is usually in a few days. I think it might have happened after a restart as well, but I restart so rarely that I'm not sure.

I have no issues with retaining my set values - it remembers them well. That's not the problem.

It works like an if-function:

if(active == default) { use active value }

This is OK, as long as the default value is a value where nothing happens anyway. The problem is that the default value changes to match my set value, rendering it useless. See the screenshot in the middle of the original post, "Core Voltage Offset", the default is no longer zero. So I have to change my set value to any value right next to the previously made useless value in order to get my 90mV undervolt back. Note that with the default at -93.75 and active at -92.77, I'm getting a 92.77mV undervolt, because the only thing that matters is that it's different from the default, not how different.

The 20% performance increase is probably a best case scenario as it's measured by a LinX. Since it uses more power than normal loads, it hits the TDP quicker, at lower clocks, at lower volts, where the 90mV undervolt is a relatively bigger change.

Although when compressing video, I have noticed that with (and only with) the undervolt, the CPU runs at full clockspeed throughout the process.

[idata]

I understand now what you were trying to explain. The way you wrote it confused me, which I now see why. You don't quite understand the way that IXTU works when you change a setting like the Core Voltage Offset.

But first, the main thing I want you to know is you are correct about why IXTU is not changing the Core Voltage Offset value you set. I will explain why that is happening, but first some information about IXTU.

The settings listed under Default in IXTU are the values set in your PC's BIOS. IXTU does NOT change the values in the BIOS. So the values listed under Default will never change, unless you change them manually in your BIOS. Or I should say, they should never change unless you manually change them in the BIOS.

The settings you change in IXTU will be shown in under Active. They will also be shown under Proposed once you click Apply.

What is actually happening is, when your PC wakes from Sleep, your PC's BIOS is using the value you changed in IXTU, and changing it in the BIOS.

What I still don't understand or see, is where the Default or Active voltage is not set to the value reduced by ~0.09V. I don't see any voltage except the word Default, which tells me nothing.

Also, if after waking from Sleep, you find the -93.75 mV Core Voltage Offset value in the Default column, that is now the value set in your BIOS, although you are saying that it has not been applied and active. That I believe is possible.

If you restarted or shutdown and booted the PC after this happens, then your -93.75 mV Core Voltage Offset value will be applied to the Core Voltage. That would explain why you "Until after a few days, the default matches my active value again".

If the value of any setting in the Default and Active columns are the same, there is no way to "change" it to the same value. That does not make sense. The Default (BIOS) value of Core Voltage Offset is set to -93.75 mV, and the Active value is the same since it has not been changed since the last restart/boot of the PC.

When a PC wakes from Sleep, the BIOS must apply all the values set in the BIOS. A common bug when waking from Sleep is the BIOS does not do that correctly. Your PC is doing that right, but is making one mistake. It is using the value you set for Core Voltage Offset in IXTU, and putting it in the BIOS.

That is what I think is happening, but I cannot confirm that since I don't have your PC. When my PC wakes from Sleep, it does not use my IXTU settings as the BIOS settings.

You can check if what I think is happening is true, by simply going into your PC's BIOS after waking from Sleep, and see if the Core Voltage Offset value is set to you IXTU setting. It should NOT be set to that value.

[APart1]

My laptop (Dell XPS 13) has no options in BIOS to change or even view anything related to voltage (or frequency).

Also, even if the BIOS did change the voltage setting to -93mV, it's not actually reducing the voltage (as confirmed by HWiNFO and performance tests), so I still need XTU to do the job.

That CLI looks promising though, might need to script something that detects when this has happened and corrects it.

[idata]

Are you experiencing this issue with version 6.0.2.8?

https://downloadcenter.intel.com/download/24075/Intel-Extreme-Tuning-Utility-Intel-XTU- https://downloadcenter.intel.com/download/24075/Intel-Extreme-Tuning-Utility-Intel-XTU-Allan.

[APart1]

Yes, 6.0.2.8 is what I'm using.

[idata]

Thank you,I have not been able to replicate this issue, perhaps, some peers will provide more details about this matter.

Allan.

[jbond5]

I face the exact same issue as ajp_anton

That is really frustrating because undervolting is very useful on laptop or tablet (mine is a Surface Pro 4 M3).

Maybe is there a way to apply desired voltage invoking XTU with a Windows task run at resume from sleep?

[idata]

Not a solution, but a possible workaround until intel finds the problem.

The XTU command line utility will let you monitor or set any values through a command line statement.

Here is an example that will list the current XTU Values:

"C:\Program Files (x86)\Intel\Intel(R) Extreme Tuning Utility\Client\xtucli" -i tuning

or --help for more information

You can run a command after sleep to tweak your value, or run it automatically every x hours !

[jbond5]

yep, I have just read a thread on Reddit on the CLI.

What I don't catch is why doesn't Intel use this method instead of something that seems to have a lot of issues since sometime with standby.

[APart1]

I've experimented with the CLI, but there are two problems.

First, the output from the CLI is weird and I haven't found a way to catch it for interpretation.

Second, there is no way to check the default value from the CLI, only from the GUI, so there's no way to know if the default value has changed. Well, I could monitor the core voltage somehow and see if it's lower than some threshold, but that's also difficult because it varies depending on the CPU activity.