C-States stopped working in Windows

[MatrixQW]

I had High Performance power profile active in Windows 10 22H2 and I turned C-States off in ThrottleStop 9.6.
Don't know what happened but using Balanced profile the cpu doesn't get out of C1 and C-States are turned on. Before I changed that it was spending most of the time in C7.
I really don't want to reinstall Windows to fix this.
Anyone has a clue to what happened?

 

[Bogus5]

So you think that TS saves the "Core C States" settings in the Windows registry and not in the configuration file?

 

[unclewebb]

that TS saves the "Core C States" settings in the Windows registry and not in the configuration file?

This is the one item that ThrottleStop does not save in the ThrottleStop.INI configuration file. If you use ThrottleStop to disable the C states, this information is saved in whatever Windows power plan that you are presently using.

@MatrixQW

I have no idea what you did but if you used ThrottleStop to turn off the C states in a power plan then you need to use ThrottleStop to turn the C states back on in that same power plan.

Switch to the power plan you want to change. Open the ThrottleStop C States window, check the C States - AC box and select either the On or the Off option and then press the Apply button. If you turn the C states On and your computer is idle, you should immediately see the C states window light up with lots of C state activity. If you select Off and press Apply, the C states monitoring data should show 0.0 for all of the C states.

C States Off

C States On

If you have any problems you can also open up the Windows Power Options, select the power plan and then press the "Restore plan defaults" button.

 

[MatrixQW]

I just restored plans to their defaults but both Balanced and High performance refuse to enter lower states. This is really strange.
All I did was turn off C-States when using High Performance profile.
I'm using Balanced right now and as you can see c3, c6 and c7 are at 0.

 

[unclewebb]

Try setting the Package C State to C7. This should not make any difference to the core C states but worth a try.

Did you try pressing the Restore plan defaults button in Power Options?

Did you try selecting C States - AC and the On button and then press Apply?

 

[MatrixQW]

1. Package C State to C7 didn't work.
2. I restored plan defaults in Windows Power Options several times. Still not going into C7.
3. I Selected C States - AC and the On button and pressed Apply. Still not going into C7.

So, ThrottleStop changed something that even restoring Windows power plan to defaults isn't activating C States or Windows itself broke something that doesn't let it activate C States.
This is really frustrating, I'm already seeing that a Windows reinstall is the only way and I don't want to do that.

 

[unclewebb]

How is your BIOS setup? If the C states are disabled in the BIOS, they will not work in Windows.

Did you try rebooting after pressing the Restore plan defaults button?

I have never had this problem and no one else has ever reported the problem that you are having. The Restore plan defaults button is designed to set the power plan exactly as it was.

 

[MatrixQW]

As I mentioned on my first message, cpu was on C7 most of the time, so they were working.
I actually did restart the PC before but no help.
In BIOS C-States are set to Auto.
I have cpu turbo mode disabled but that shouldn't affect C-States.

I was using Windows High Performance profile when I turned C-States off in ThrottleStop and when I changed Windows profile to Balanced, I noticed that C-States option was On in TS but C7 was at 0.
It seems to have completely disable it,
My board is Asus Z97K and cpu i5-4690K.

 

[unclewebb]

Instead of using Auto in the BIOS set the C States to enabled.

I have cpu turbo mode disabled but that shouldn't affect C-States.

Try setting turbo to enabled in the BIOS. There is some sort of incompatibility between how your BIOS is setting up the C states and how Windows is setting them. The problem is probably the BIOS.

 

[MatrixQW]

You are correct, enabled in BIOS they work. Strange thing is they were working with auto when I installed Windows.
In BIOS I have Enhanced C1 but in TS the C1E is not ticked as you can see in these pics. Why is that?
And now in demotion/undemotion, C1/C3 are ticked but not PKG. What are these for?

I'll answer myself the first question: I had to delete ThrottleStop.ini so it can read correctly the values BIOS gave the OS.
Since I have a Z97-K board and a K cpu I can disable C-States and cpu turbo mode keeps running.
This is nice, I keep the performance without added latency from transitions.
I just want to disable C-States when using High Performance profile in Windows.
Does C1E also gets disabled and cpu enters C1 state only ? This would be ideal.

 

[unclewebb]

Strange thing is they were working with auto when I installed Windows.

On some motherboards the meaning of Auto can randomly change. One moment Auto means enabled and then you make a completely unrelated change to something and Auto for the C states changes to disabled. That is why it is best to specifically set the C states in the BIOS to either enabled or disabled.

but in TS the C1E is not ticked as you can see in these pics.

If you make any changes in the BIOS, you need to delete the ThrottleStop.INI file so ThrottleStop can read the updated value from the CPU. If you do not do this, ThrottleStop will use the previous value that you were using in ThrottleStop and will ignore any BIOS changes you have made. That might be the problem with C1E or maybe your BIOS is not setting C1E correctly.

demotion/undemotion, C1/C3 are ticked but not PKG

These settings control how quickly a core will transition between C states. For early Core i processors from 15 years ago, these settings made a big difference in the percentage of time a core spends in the various C states. For your 4th Gen CPU and especially for newer CPUs, demotion and undemotion seems to make very little difference to anything. You can try checking different boxes, hit Apply and see if it makes any difference to what C states are being used. For maximum time in C7, I check the three undemotion boxes on the right side. This might not be best. The differences were so small that I reached a point where I lost interest in these settings.

Does C1E also gets disabled and cpu enters C1 state only ?

If the C1E box is clear in ThrottleStop and the rest of the C states are disabled, the CPU cores will have a choice of being in C0 when the CPU is working on a task or the core will be in C1 when not working on a task.

If core C3, C6 and C7 are disabled, Intel Turbo Boost will not work correctly. The maximum multiplier will be limited to the 4 Cores Active multiplier listed in the FIVR window. The maximum multiplier when 1 Core is active is not available when C3, C6 and C7 are all disabled.

 

[MatrixQW]

Thank you for explaining everything.
One note is I already mentioned that cpu turbo mode doesn't get disabled with a Z/K board/cpu if C-States are disabled.
As you can see the cpu multiplier is 39, turbo is running and C-States are off.

 

[unclewebb]

cpu turbo mode doesn't get disabled with a Z/K board/cpu if C-States are disabled.

That is correct.

I always forget to mention that disabling the C states only limits turbo boost on the non K CPUs or on K series CPUs when they are being used on a non Z series board.

The ability to disable the C states is a useful ThrottleStop feature. You should be able to create a Windows power plan for maximum CPU speed and minimum latency with the C states disabled. You can then switch to a different Windows power plan with the C states enabled to reduce power consumption and heat. No need to reboot to toggle the C states on or off. Hopefully everything is working correctly and you can finally do that now.

 

[MatrixQW]

If the C1E box is clear in ThrottleStop and the rest of the C states are disabled, the CPU cores will have a choice of being in C0 when the CPU is working on a task or the core will be in C1 when not working on a task.

I asked "Does C1E also get disabled and cpu enters C1 state only ?".
In BIOS, C1E is inside C-States and so I would expect by disabling C-States in ThrottleStop that C1E would not be in effect but this is not what happens and with a side effect or bug.
The cpu multiplier isn't a steady 39, keeps fluctuating and never reachs 3.9GHz.
This is with Windows power plan in High Performance.
With C1E disabled in BIOS it works as I expect it, like it shows in my previous screenshot.
Here is a screenshot with C1E enabled.

 

[unclewebb]

I would expect by disabling C-States in ThrottleStop that C1E would not be in effect

You might expect that but that is not how ThrottleStop works.

In ThrottleStop, C1E and the rest of the C states are controlled separately. I prefer this so you can disable all of the other C states using ThrottleStop and then can easily toggle just C1E on or off. Your screenshot shows that C1E is enabled. Use ThrottleStop to clear the C1E box and then your multiplier should be a steady 39.00.

a side effect or bug

A bug is when software is doing something unexpected. In this case, the ThrottleStop C state options are working exactly as I want them to work.

 

[MatrixQW]

I'm not saying ThrottleStop doesn't work as it is designed but rather C1E itself has a side effect.
Windows High Performance power plan with both C-States and C1E enabled or disabled the cpu multiplier is steady at 39, wich indicates that C1E depends on C-States to have the same behaviour.
But by disabling C1E in TS as a separate global option we can't have it set differently depending on the power plan used like C-States does, so when using Balanced profile with C-States enabled the C1E will be disabled.

 

[unclewebb]

But by disabling C1E in TS as a separate global option we can't have it set differently depending on the power plan used like C-States does

The ability to toggle C1E on and off is a separate adjustment within the CPU. I do not know how to toggle C1E on and off by making changes to the Windows power plan.

Using the BIOS to enable or disable C3 / C6 / C7 uses a different control method compared to making changes to the Windows power plan to toggle C3 / C6 / C7 on and off.

when using Balanced profile with C-States enabled the C1E will be disabled.

I understand what you are saying but you can use ThrottleStop to work around this limitation. Here is an example.

If you want C1E to be disabled when using the Windows High Performance power plan and you want C1E to be enabled when using the Balanced power plan, try setting up two different profiles within ThrottleStop.

Set Profile 1 to the High Performance power plan with C1E toggled off and set Profile 2 within ThrottleStop to the Balanced power plan with C1E toggled on.

You can also use ThrottleStop to toggle C3 / C6 / C7 on or off in any Windows power plan.

There should be a way to setup the C states however you want them setup by using ThrottleStop.

 

[Master_X]

The ability to toggle C1E on and off is a separate adjustment within the CPU. I do not know how to toggle C1E on and off by making changes to the Windows power plan.

Using the BIOS to enable or disable C3 / C6 / C7 uses a different control method compared to making changes to the Windows power plan to toggle C3 / C6 / C7 on and off.


I understand what you are saying but you can use ThrottleStop to work around this limitation. Here is an example.

If you want C1E to be disabled when using the Windows High Performance power plan and you want C1E to be enabled when using the Balanced power plan, try setting up two different profiles within ThrottleStop.

Set Profile 1 to the High Performance power plan with C1E toggled off and set Profile 2 within ThrottleStop to the Balanced power plan with C1E toggled on.

You can also use ThrottleStop to toggle C3 / C6 / C7 on or off in any Windows power plan.

There should be a way to setup the C states however you want them setup by using ThrottleStop.

Hey there I thought I revive this post once because I have a question. I noticed my computer will not use the C states properly and I remembered Throttlestop. The 13600K always clocks at 5100Mhz or "demands" this clock. Effective clocks in HWinfo are way lower. However this causes the CPU to take minimum 30W.

Starting Throttlestop and only checking the Speed Shift EPP (not clicking save) fixed this and the CPU power draw goes down to minimum of 10W. Since I did nothing but checking this one checkbox can you explain what happens there? I can even close Throttlestop after this and it's staying like this until every reboot. The clock speeds are then stuck again until opening and closing Throttlestop once.

Thank you

 

[unclewebb]

I noticed my computer will not use the C states properly

What does that mean? If you noticed something unusual, post a screenshot of ThrottleStop with the C States window open while your computer is idle at the desktop. If the ThrottleStop C States window shows 0.0 for all of the C states, check the BIOS. Are the C states enabled in the BIOS?

If you are using the default Windows High Performance power plan, the CPU should run at max speed when it is lightly loaded. That is the purpose of the High Performance power plan. Use the Windows Balanced power plan if you want the CPU to slow down when it is lightly loaded. Windows should be able to handle this perfectly fine without needing to use ThrottleStop.

If the Balanced power plan does not seem to be working correctly, open Power Options and press the Restore plan defaults button. This should set the Minimum processor state to 5% which should allow the CPU to slow down when idle. Some people have too many useless tasks running in the background 24/7. Intel CPUs are not designed to slow down if they have a task to perform. What does ThrottleStop report for idle C0%?

 

[Master_X]

What does that mean? If you noticed something unusual, post a screenshot of ThrottleStop with the C States window open while your computer is idle at the desktop. If the ThrottleStop C States window shows 0.0 for all of the C states, check the BIOS. Are the C states enabled in the BIOS?

If you are using the default Windows High Performance power plan, the CPU should run at max speed when it is lightly loaded. That is the purpose of the High Performance power plan. Use the Windows Balanced power plan if you want the CPU to slow down when it is lightly loaded. Windows should be able to handle this perfectly fine without needing to use ThrottleStop.

If the Balanced power plan does not seem to be working correctly, open Power Options and press the Restore plan defaults button. This should set the Minimum processor state to 5% which should allow the CPU to slow down when idle. Some people have too many useless tasks running in the background 24/7. Intel CPUs are not designed to slow down if they have a task to perform. What does ThrottleStop report for idle C0%?

View attachment 342527

Thats a longer answer than I thought but thank you already. C States are defenetely enabled in BIOS.

Indeed I been using high performance power plan. That was the first thing I did not know really does something else in the background. I always thought it only changes the advanced settings in the picture you posted. I always set min/max CPU to 0 and 100% and thought this is the relevant setting. I now noticed this setting seems to do no change at all but changing the power plan does it. Energysaving plan would lock the speed at max 2500Mhz and the balanced one does a little downclocking as you described. However checking that Speed Shift EPP does a better job in balanced or high power plan regarding power usage. Balanced sets it around 20W.

Do you know if I can set the Speed Shift EPP thing manually and forever without Throttlestop? That would be what I like to do.

If I can reconstruct it correctly C0% is around 1-3 when in high performance plan and after checking the Speed Shift EPP it's between 8 and 11. Changing the plan to balanced without Speed Shift EPP option checked it's around 6.

Pretty confusing this power plan stuff - at least not working the way I always thought it does

 

[unclewebb]

Do you know if I can set the Speed Shift EPP thing manually and forever without ThrottleStop?

I do not know how to do that in Windows 11.

I always set min/max CPU to 0 and 100%

I would use the default values for whatever power plan you are using. If you use the default Windows High Performance power plan then you can set a Speed Shift EPP value using ThrottleStop. You can edit the EPP value on the main screen of ThrottleStop by clicking on it.

C States are definitely enabled in BIOS.

But are they actually being used when your computer is idle? That is why I asked you to post a screenshot of the C states window.

The main problem is you have lots of stuff running in the background. Intel designs their CPUs to almost instantly go up to full speed so they can quickly process background tasks. This used to be an efficient way to process these tasks. With the sky high power consumption of Intel's recent CPUs when they are running at full speed, perhaps Intel needs to rethink this.

 

[career]

Having the new Core Ultra 7 and 9 CPUs Intel has already done it. New Core Ultra provides more power efficiency compared to previous series due to its updated architecture and tasks pipeline logic. Benchmarks mostly prove the fact that it is more efficient than other Intel's. That is all, of course, related to laptops only. To do 13600K as more power efficient could be quite a quest.

​

 

[Master_X]

But are they actually being used when your computer is idle? That is why I asked you to post a screenshot of the C states window.

Sorry I forgot these. Hope the screenshots are showing what you meant. First is with that checkbox checked on high performance plan second one after changing the powerplan back and forth without checking the option.

Edit: I think I am to less into this topic but I thought if the CPU clocks down this happens by C States. I somehow think this is wrong or not all of it. And also for the first screenshot the clockspeed goes also down to 1107Mhz. Just wanted to mention it goes way below the 3.1Ghz shown.

 

[unclewebb]

I thought if the CPU clocks down this happens by C States

The active CPU cores clocking up or down is separate from the C states. Your screenshots show that the low power C states are working correctly.

the clockspeed goes also down to 1107Mhz. Just wanted to mention it goes way below the 3.1Ghz shown.

What monitoring app are you using to monitor the MHz? When a CPU is lightly loaded, ThrottleStop does a really good job of accurately reporting the MHz. ThrottleStop uses the Intel recommended monitoring method. You can trust what ThrottleStop is showing you. Many other popular monitoring apps including the Task Manager are not nearly as accurate.

Your first screenshot shows that the first core was loaded and the average multiplier used during that one second time interval was 31.82 for the first thread of the first core. There might be inactive cores averaging 1100 MHz. That is meaningless though if there are active cores running much faster than that.

Many monitoring apps get confused when a CPU is lightly loaded and some of the individual cores are sitting dormant in one of the low power C states. In this state they can be disconnected from the internal clock so some individual cores might spend 99% of their time sitting at 0 MHz. Reporting MHz data when a CPU core is dormant does not give a very accurate look at what the CPU is really doing internally.

You should open the Task Manager and find out what is running in the background on your computer. When you think your computer is idle, it is not idle at all. There is lots of stuff running in the background keeping cores busy. This is what causes the CPU to want to jump up to max speed.

Only 4.3% in the C0 state does not seem like much to most people but it really is. There is lots of room for improvement. Your idle CPU is spending 50 times more time processing background tasks compared to what my idle CPU is doing. Work on that if you are interested in reducing your idle power consumption and idle temperatures.

An idle computer can have the individual cores averaging up to 99% of their time in C7.

 

[mpelley92]

Hopefully it's okay to revive this thread from earlier this year.

I really wanted to help others who have come across issues like this, especially with a program like ThrottleStop.

My theory is that this program somehow permanently changes certain BIOS options. This theory comes from an issue I've had with my Alienware 17R5 not reverting back to defaults (for core ratios, C1E, EIST settings) even after uninstalling ThrottleStop.

Those who have one of these Alienware laptops knows that it has very limited BIOS options when it comes to modifying CPU features, frequencies, voltages, C-States, everything you would expect to be able to change on a performance laptop.

Moreover, changing settings using a program like ThrottleStop seems to somehow lock the BIOS into unchangable modes that persist, even through a reinstallation of Windows (as I learned).

I have remedied my problem by setting the BIOS to default options.

This is certainly a pain to someone who has carefully customized the BIOS on a desktop or a power-user-friendly laptop, but for me with my Alienware, it was easy (I only really change about 2 or 3 settings from default).

The only reason I really found this solution was because I was so discouraged by the poor thermal performance (and then not being able to switch back to default behavior), I was ready to sell my laptop to anyone wanting to buy it. I reset the BIOS as a prerequisite as I do with any desktop/laptop before sale, and when I reinstalled Windows, I noticed that HWiNFO was reporting stock clocks again, as well as a lower idle power usage.

Since this discovery, I have switched to Intel XTU. That program is much friendlier than ThrottleStop, and allows you to actually change the voltage offset (for some reason ThrottleStop could not change the offset on my Core i9-8950HK). These changes also persist similar to ThrottleStop, however, they do not modify C-States or EIST values in the BIOS.

Anyhow, hopefully this helps someone else who has experienced this issue!