Why are all my cores running at the same speed?

I have a i7-7700k, not overclocked. It's supposed to run at 4.2GHz, 4.5 with turbo boost. Now when I go to Chrome console, and run "while(true);" to hammer one core, I would expect that core to hit 4.5GHz, and the others to remain at the normal idle speed of 800MHz. However for some reason all the cores run at 4.4. This is disturbing, because I would like that core to reach 4.5. Here's a screenshot of HWMonitor, where you can see that only CPU #7 is running, yet all have a frequency of 4400MHz:


Any explanation would be appreciated.

Turbo is a funny beast that needs certain conditions met before it activates. I'm not familiar with that benchmark but If you can isolate it in task manager and set affinity to one core you might see what you want

Thank you for your reply. Here is what I tried: Task Manager was showing Chrome at 13% which is a full CPU. I set the affinity to only CPU #7. HWMonitor now still shows all cores at 4400MHz, but every now and again, maybe 20% of the time, Core #3 (which contains CPU #7 as in my screenshot above) goes up to 4.5MHz. I wonder why the others cores are running at such a high speed when I'm only using #3.

What do you have the windows power setting on? Balanced, performance?

It was on Balanced, but I just now tried Performance & Power Saving, and nothing changed.

Personally I wouldn't waste too much time on it. The turbo function will work according to what the CPU/motherboard tells it.

You might also watch the core frequency report in the CPU-z tab "CPU" while stressing the CPU.

CPU-z shows the same. I guess it's not important, the 100MHz difference is not a big deal.