CPU Refuses to Turbo

[ThyFreaK]

Hey guys,

Hope you're all well.

I've got an Intel i7 8086K in my rig that a few years ago I know would turbo up to 5.1/5.2GHz which was awesome

 

The only issue with it is now it won't turbo at all, locked at 4GHz for some reason and won't budge when put under load

I can adjust the base frequency and move that up to ~5GHz but I'd rather it sit at 4GHz and turbo up to 5GHz like it once upon a time would have.

 

I've reset my BIOS and still nothing, unfortunately - any suggestions?

[Leandro Fernandes]

Without knowing any configurations, it could be anything from Bios settings to temperatures.

Lets start with what's you motherboard model, temperatures under load and which power plan is selected in windows?

[ThyFreaK]

10 minutes ago, Leandro Fernandes said:

Without knowing any configurations, it could be anything from Bios settings to temperatures.

Lets start with what's you motherboard model, temperatures under load and which power plan is selected in windows?

I've got an Asus ROG Strix Z370-E, the CPU tops out at ~60 degrees and it's running a high-performance power plan.
I've attached a screenshot of the XTU graph and ThrottleStop taken whilst running Cinebench where the frequency is basically static

[Leandro Fernandes]

I believe for your case you should lock the CPU Cores at the desired speed. Intel's Turbo feature is a bit temperamental. You can try to lock it at 5Ghz and check the temperatures under load, if they reach over 90, it could be one of the reasons it doesn't go higher than 4Ghz with Intel Turbo.

 

Somethings that might work:

Disable ASUS MultiCore Enhancement

Disable Intel SpeedStep

Enable Turbo Mode

 

While running the OS choose the High performance plan.

 

[unclewebb]

@ThyFreaK

 

Exit XTU. Running ThrottleStop and XTU together at the same time is not a good idea because they can be writing different values to the same CPU registers.

 

6 hours ago, ThyFreaK said:

I'd rather it sit at 4GHz and turbo up to 5GHz like it once upon a time would have.

You might be able to accomplish the same thing by adjusting the Windows power plan. Try setting the Minimum processor state to 99%. That will disable Intel turbo boost so the CPU will run at a minimum of 4000 MHz. Leave the Maximum processor state at 100% so the CPU can still turbo boost to 5.0 GHz.

 

 

If you plan to run ThrottleStop all of the time, use the default Windows High Performance power plan with both Min and Max processor states set to 100%. This will help prevent Windows and ThrottleStop from fighting over control of your CPU.

 

Try setting Speed Shift Min to 40 and Speed Shift Max to 50. That might get you the range you are looking for.

 

 

When running Windows 11, this may not work correctly anymore. It might cause a fight between ThrottleStop and Windows where they are both trying to control the min and max CPU speed. Use the default Windows High Performance power plan and then on the main ThrottleStop screen check the Speed Shift EPP box and change that from 128 to 84. This should override the High Performance plan settings so it is not pegged at 5000 MHz when lightly loaded or idle. 

 

Show me screenshots of your ThrottleStop TPL and FIVR windows so I can see your settings.

 

If you have the low power C states enabled in the BIOS, there is no need to use these tricks to slow the CPU down. The C states reduce CPU power consumption and idle temperatures automatically. When a core has something to do it will run at 5000 MHz and when it has nothing to do it will enter C7 where the core will be dormant at 0 MHz and 0 volts. This all happens automatically if you enable the C states. 

 

Fast cores or slow cores makes little difference to heat or power consumption when the C states are enabled. I prefer to run at full speed when a desktop computer is plugged in.

 

[ThyFreaK]

On 5/4/2023 at 3:49 AM, unclewebb said:

@ThyFreaK

 

Exit XTU. Running ThrottleStop and XTU together at the same time is not a good idea because they can be writing different values to the same CPU registers.

 

You might be able to accomplish the same thing by adjusting the Windows power plan. Try setting the Minimum processor state to 99%. That will disable Intel turbo boost so the CPU will run at a minimum of 4000 MHz. Leave the Maximum processor state at 100% so the CPU can still turbo boost to 5.0 GHz.

 

 

If you plan to run ThrottleStop all of the time, use the default Windows High Performance power plan with both Min and Max processor states set to 100%. This will help prevent Windows and ThrottleStop from fighting over control of your CPU.

 

Try setting Speed Shift Min to 40 and Speed Shift Max to 50. That might get you the range you are looking for.

 

 

When running Windows 11, this may not work correctly anymore. It might cause a fight between ThrottleStop and Windows where they are both trying to control the min and max CPU speed. Use the default Windows High Performance power plan and then on the main ThrottleStop screen check the Speed Shift EPP box and change that from 128 to 84. This should override the High Performance plan settings so it is not pegged at 5000 MHz when lightly loaded or idle. 

 

Show me screenshots of your ThrottleStop TPL and FIVR windows so I can see your settings.

 

If you have the low power C states enabled in the BIOS, there is no need to use these tricks to slow the CPU down. The C states reduce CPU power consumption and idle temperatures automatically. When a core has something to do it will run at 5000 MHz and when it has nothing to do it will enter C7 where the core will be dormant at 0 MHz and 0 volts. This all happens automatically if you enable the C states. 

 

Fast cores or slow cores makes little difference to heat or power consumption when the C states are enabled. I prefer to run at full speed when a desktop computer is plugged in.

 

Thanks for the reply.

Have taken the steps you've advised and still no ball unfortunately

Photo of TPL:

 

Photo of FIVR:


Do you believe the C States could be limiting the CPU from hitting its turbo? I've got XTU closed as you mentioned and am running a Cinebench test as this photo was taken:

[unclewebb]

10 hours ago, ThyFreaK said:

still no ball

It looks like Windows 11 is not setting your CPU up correctly. 

 

When Cinebench is running, does Limit Reasons show anything lighting up red? Your previous screenshot showed EDP OTHER lighting up red under the RING column which should not be happening. I think that is only throttling the ring MHz though. You can look in the FIVR monitoring table to see what Cache Ratio is reported while Cinebench is running.  

 

In the FIVR window, press the 50 button in the All Core section. In the TPL window, check the MMIO Lock box. This feature has some special code to remove a hidden maximum multiplier limitation. Hopefully this works because other than that, I am not sure why your CPU is not able to use the maximum multiplier.

 

When testing, make sure you are using the Windows High Performance power plan with it set to default values. There is a Restore plan defaults button that you can use. Double check that the Min and Max processor state are both set to 100%.  

 

If you don't make any progress, I have a tool that can dump all the values of the various CPU registers. There might be a clue hiding in that info.