single thread performance on new Intel processor - turbo boost inverted?

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I apologize in advance if this seems out of place but I do think it relates to this list as the app I am referring to is Houdini.

I am fortunate enough to have a shiny new dual 8 core Xeon workstation, manufactured by Lenovo. The cpu are the 6134 model with a base frequency of 3.2 and so called turbo mode of 3.7.

My understanding of these processors is that they will increase frequency (turbo boost) when running single threaded apps. However I seem to be getting just the opposite effect on my machine.

When running scenes with (assumed) single threaded routines my cpu clock speed is actually throttled lower, at least according to Task Manager. ie as CPU core utilization decreases so does clock speed.
During some processes the clock will actually decrease to the low 2's Ghz or even lower. It is only when I can load my cores with a multi threaded process or render that I can ever see the speed top 3.5Ghz.

Am I looking at this incorrectly or is there possibly something amiss with my machine?

I have checked the bios and turned off all power saving settings.

thanks in advance for any insight into this
jammer
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That does seem odd - do you have a CPU temperature monitoring app that you can use to see if it's due to thermal throttling?
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Download HWiNFO: https://www.hwinfo.com/download.php [www.hwinfo.com]

It can tell you the frequency that each core is running at and the temperature of your CPUs, along with a host of other data. You can change the refresh frequency to get more interactive updates (default is 2000 ms I believe).
Clock speeds dipping could be a result of the power management mode you have selected in your OS, although it should dip during idle, not during load.
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thanks for this info

I installed HWiNFO and from what I can see I have a theory.

Not being real technical savvy I may be misrepresenting this but it appears that the thread or threads quickly hop from core to core so that the cpu speed I am seeing in the windows task manager is an average of all the cores, not a representation of the speed for the fastest cores.

The individual cores when active do indeed peg out at just under 3.7Ghz but for only a brief moment before maxing out a different core.
The “idle” cores then move to a very low speed which is not surprising.
The more threads working, the more often the individual cores are maxing out and this is reflected in the higher overall speed shown when doing something like a render.

Task manager is showing an average speed for all cores, not the maximum for individual core(s)

So long story short I think all is as it should be.

thanks again
jammer
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