i7 7700k odd Turbo Speed question

[Legless]

I've just upgraded my motherboard and cpu and have a question about the Turbo speed of the i7 7700k. It's listed as 4.2Ghz at stock and with the default Turbo settings in the bios it should be doing 4.5Ghz.

I've noticed that in Windows, when i set the power plan to Balanced (in the windows settings), the cpu runs at 800Mhz idling and 4.4Ghz when benched.

When i set the power plan to High Performance, the cpu runs at 4.5Ghz all the time (as expected), but as soon as i bench it, the speed drops down to 4.4Ghz. Why does this cpu not stay at 4.5Ghz when stressed?

When looking at CPU-Z whist benching the cpu, I've noticed that the multiplier drops from x45 to x44 and the voltage also drops a small amount.

Any help, much appreciated.

 

[fastboy]

is it the avx offset?

 

[Legless]

AVX offset is set to 0.

I looked on Google and found an interesting post. It said that if using the default stock settings in the bios, having Speedstep and Turbo Mode set to Auto, the overclock on the cpu will only jump from 4.2GHz to 4.5Ghz if 1 core is running at full speed, so when benching and stressing all 4 cores, the i7 7700K will only run at 4.4Ghz.

Can someone confirm this, as if it's true, then my system is working fine with stock settings and i'm happy with that, until I can scrape the money together for a new GFX card and manually overclock the system.

 

[fastboy]

mine goes to 4.4 on all cores using the cpu--z bench test using 'load optimised settings' in the bios