I'm havving issues with a brand new Precision 3620 workstation.
The processor is an Intel 6700K 4Ghz base clock and 4.2Ghz turbo clock.
1) For any kind single threaded task it always runs at 4Ghz and never at 4.2Ghz.
How can I make it run at turbo speed (bios is set so it should) ?
2) For multithreading tasks using all cores (also using SIMD) the clock drops to 3.6Ghz
Using Intel power gadget I measure 60Watt power consumption and 54 degrees C.
(Test is Prime95 using blend mode test, so not max heat small FFT test)
I find this clock behavior quite unacceptable for a PC sold as workstation.
Using the Intel Extreme Tuning tool I can fix issue 2) by rasing the Processor Core IccMax from 92A to 110A. This indicates wrong CPU setting in the bios, but these hidden settings are not visible to be changed.
Issue 1) I can not fix.
Is there any way to correct these issues ?
Turbo boost is burstable. There isnt any way to lock it at the max turbo speed. The thermal activity sets the speed and when they get hot intel cpus slow down. What you are asking for isnt supported by INTEL or Dell. The increased clock rate is limited by the processor's power, current and thermal limits,as well as the number of cores currently in use and the maximum frequency of the active cores.
What is happening is the way the processor is designed. As the number of used cores goes up and the load goes up the speed goes down.
That is all true but does not answer the question
1) With light load like single threading, indeed the processor should be able to run at turbo speed
2) On high load without reaching high temperature as mentionned the processor should not run below base clock.
These both are issues that should not occur.
Likely Dell is to blame, I would reccomend contacting Dell (as unfortunately Dell doesn't answer questions on this forum)
Just thought I'd mention - also a 3620 here and seeing the same behavior with never going into Turbo. The reason for getting the 6700K was for the clock speeds, so it's a bit disappointing. At least it's a higher base-frequency than the 6700. Likely Dell went for stability in this choice, but really, seems totally overkill.