Pretty sure this is normal behavior for pretty much any modern CPU.
But never really paid attention to it until recently.
On both my gaming rig and workstation machines I noticed that CPUz shows the base clock bouncing between 3.5 and about 5.4 GHz
My gaming rig is running the 7800X3D and my WS is running a 7950X and they both are showing very similar behavior.
I would imagine that Intel CPU’s would be showing something like this too ?
Yup, it is common for a system to be configured such that the OS dynamically adjusts the CPU clock depending on load to save power, less heat, etc.
In windows it may be called “performance mode” or similar under the power settings e.g. “balanced”… On Linux there are various “governor” configurations possible to try to min/max power saving and preserving snappiness.
My 9950X can boost to just over 5.7GHz under low thread count loads, but idles at just 600MHz when nothing is going on. Its fun to watch the CPU temperature on the motherboard (or just listen to the chassis fans change speed) and the frequency of the CPU to get a feeling for how your system is tuned and performing.
Yeah thanks for the feedback, I figured it was something like this.
Now I also noticed that CPUz shows a multiple range too, my CPU’s both show as starting at 4 up to 54 so I would think this would be 400MHz ~ 5.4GHz
Right, the CPU Core Speed is calculated by the Bus Speed times the Multiplier.
Here is an example CPU-Z for a 7950X like yours. Assuming you haven’t done any odd BIOS over/under clocking of an unlocked bus speed, it will likely be similar looking:
Assuming a 100MHz bus speed, then x4.0 multiplier would suggest a 400MHz speed (probably idling). The min/max speeds can depend on BIOS and pstate drivers etc.
Fun stuff! Enjoy poking around under the hood with tools like CPU-z, hwinfo64, etc, a great way to learn what all is going on!
Dynamic CPU clock is a feature to save power comsumption. It is called “AMD Cool N Quiet”. It is enabled when the Windows is not in “Best Performance” profile. You can disable it in the bios as well. On the intel side, this feature is labled as “SpeedStep”.