7700K Underclocking, ThrottleStop

Hello,

I have 7700K which runs fine at full-performance mode. I'd like to setup eco/low power/quiet mode and limit max clock to 3GHz so no sudden usage spikes could increase package power above certain level, and, let's say I could leave computer working slowly but steadily whole night without worrying about power usage and noise.

I played with ThrottleStop and used Set Multiplier option to limit it to 3Ghz, but strange things happen.

First, it won't go much below 3GHz when Set Multiplier is enabled despite low load in idle. When I disable this option, it can go up to 4.5GHz on load and then downclock itself to 900MHz, which is fine. I'd like to keep this behaviour, but with 3GHz instead of 4.5GHz. Is it even possible? Package power stays well between 12-15W in idle, which is weird, as nothing happens. When Set Multiplier option is disabled it can get lower.

Another thing: How to read ThrottleStop's C States percentage correctly? What I see is:



Which number is true? What's the difference between Core C State Percent and Package C State Percent? Why C3% and C6% stay at 0 while Core C State Percent clearly says that C3 is used? Or is it?

I have C States enabled in BIOS.

 

There is a 700+ page thread dedicated to ThrottleStop on Notebook Review. It is best to post your questions about ThrottleStop there.

http://forum.notebookreview.com/threads/the-throttlestop-guide.531329/page-717

Head over there and post a picture of how you have ThrottleStop setup.

It sure is possible. You can use either Speed Shift or SpeedStep to control the maximum speed of your CPU. Modern CPUs like your 7700K support Speed Shift and I would recommend enabling that in the Turbo Power Limits window. Once enabled, you can set your Min and Max Speed Shift values there. A Max value of 30 should get you about 3000 MHz. After that, head out to the main screen and you should see SST in green. Set the Energy Performance Preference (EPP) to a number like 80 and this should give you what you are looking for. When you want to go back to full speed, change the Max value back to 45 and change the EPP value back to 0.

As for C States, the 4 individual cores can enter various C States and once all 4 cores are in the same C State, then the entire package can enter that C State. The problem is that on desktop CPUs, a lot of motherboards seem to block some of the deeper package C States from being used. My desktop is also limited to package C2. The problem can be with the motherboard or the CPU or the GPU or one or more bad drivers. Trying to find the exact cause is often times a futile search. If you have set your bios to use the deepest possible package C States and all you ever see is package C2 then I guess you are out of luck. It often times does not make a significant difference so I wouldn't worry too much about the package C States. The individual cores being able to go into C7 is far more important when it comes to reducing power consumption.

My 4700MQ supports package C6 but nothing beyond that. When a computer is idle, the individual cores can spend over 99% of their time sipping power in C7. Most people have way too much crap running on their system to ever achieve this. Bad drivers and over zealous antivirus programs are big offenders.

 

If you want lower temperatures and lower noise how about undervolting your CPU while leaving the multipliers alone at stock settings. That way you get full performance at reduced noise. Better yet delid your CPU with liquid metal to reduce temps by 10 to 15 degC. Combine that with undervolting and it should be completely silent while at full performance levels.

 

Thanks a lot, Speed Shift is exactly what I was looking for. Also ThrottleStop thread looks very insightful!