IMPORTANT Core frequency reading in Windows 11

Nothing new here, but if you have a newer CPU generation (11th gen+) then it should not be affected. Or you can disable HVCI anytime.
That should be OK, but hard to predict how HVCI will behave there. The result doesn't seem to be consistent, so you might need to disable it if you see issues. AFAIK upgrade to Win11 doesn't automatically enable HVCI.
I have done some more testing, so here the results:
- This issue affects 10th Generation (Comet Lake) and earlier CPUs. 11th generation CPUs (Ice Lake, Rocket Lake) support an alternate way to read BCLK and that seems to work properly.
- The culprit is the Core Isolation feature - when enabled (which is the default setting in Windows 11), it will block a certain interface that needs to be used on 10th generation and earlier CPUs.

So my advice is to disable the "Core Isolation" feature if you you're affected by this and need to see correct BCLK
Core Isolation was disabled on my PC and I still had the issue. Current Win11 build is 22621.382 (22H2).
There are some indications that Microsoft might relax this restriction in later builds of Windows 11, so BCLK readout should again work even with Hyper-V/HVCI.
I have the same problem, My CPU is 6700K and when I turn on CPU Virtualization HWiNFO show CPU frequency incorrectly but as you can see in picture Aida64 OSD panel show correct CPU frequency.
Hyper-V and Core isolation is off.
Windows 11 22H2

13900k, virtualization disabled. Latest Win11 22H2:



Software like Windows' Resource Manager and Process Explorer get confused, too.
But how can Core Utility be 86.4% (with some core reporting over 1005) while Core Usage is 4.6%? Obviously the cores are used more than about 5%, which my fans ramping up agree with.
Some Windows counter seems to be broken concerning CPU load and how various software like HWinfo measure it?!

Process Explorer is affected the worst, because you cannot use its Threads display properly anymore. But HWinfo also shows more zeros than usage, which is not correct. Look the the Cycles Delta vs. supposed CPU usage in PE.


Are you suggesting that 5% CPU Usage is correct while running highly multi-threaded AI image upscaling then, even while my CPU temps increase and C states don't match? The load is real, the measurements are all rather misinforming for the time being, be it HWinfo or other software.
Those are different metrics and each of them has certain advantages/disadvantages due to the way how modern CPUs work.
I fail to see the advantage of reporting 5% when the real CPU usage is over 60%, though?! This seems like a complete bogus number, neither relating to real load nor C state percentage. W11 tends to shifts more and more load from P cores to E cores so load decreases over time, but here is a screenshot of the real CPU load when all C states (Processor Idle) are disabled:

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HWinfo gets super confused by my current test setup: all cores max 60x, turbo max 60x for 2 (!) concurrent cores (60/60/59/58/57/56/55/55), all C states except C6 disabled (including C1E), all E cores disabled.
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