400% difference in CPU usage between "Task Manager" and "Sysinternal's Process Explorer"

Bertrand K 51

On one specific server I have 400% difference in CPU usage between "Task Manager" and "Sysinternal's Process Explorer" (both picture taken on the same screenshot, so at the exact same time).
What can be the cause of this discrepancy?

Process Explorer is ran with elevated privilege. But same result if ran as regular user.

Neo 421 Reputation points

2022-10-14T12:39:36.627+00:00

Same observation here. Hope it will be fixed soon.

Windows 11 Pro with latest updates.
杨岑 171 Reputation points

2022-11-09T03:45:01.157+00:00

Latest 7.0.1 still has wrong CPU usage.
杨岑 171 Reputation points

2022-11-09T06:06:10.197+00:00

There is an odd thing about the CPU usage graph. I have "Show one graph per CPU" checked, and the first graph is correct, the rest ones are not correct.
Brok3n Cogniti0n 20 Reputation points

2023-04-11T20:15:41.88+00:00
Is there any response to this? This is a bug present on Windows 11, I believe. HIWinfo64 also shows the "incorrect" CPU usage, and so do a number of other utilities. Microsoft's Task Manager and MSI Afterburner keep showing the correct figures as it was always the case. I don't think the explanation of "Task Manager is lying" is correct; there are cases when I am in a game with the CPU using 70W and being quite hot, obviously under load, and Procexp shows 1% usage, while the CPU is at max turbo speed and about 70-80% usage in reality. Some tasks are correctly estimated, for example running a prime95 stress test. Other tasks, most often games, do not show the correct usage at all. From MSI Afterburner dev:

CPU usage data sources in internal HAL were temporarily swithced to alternate NtQuerySystemInformation(SystemProcessorIdleInformation) source to bypass currently broken idle time reporting in NtQuerySystemInformation(SystemProcessorPerformanceInformation) in current 22H2 builds. Legacy CPU usage calculation implementation can be selected by power users via CpuUsageCalc config entry if necessary (for testing future (hopefully) fix in NtQuerySystemInformation(SystemProcessorPerformanceInformation) from Microsoft side). Also the same entry can be used to switch CPU usage to \Processor Information% Processor Utility perofromance counter to exactly match task manager's readings (which is not recommended, because it is base clock frequency scaled there).
Ade Iming 5 Reputation points

2023-07-01T01:52:48.2566667+00:00

same here

6 answers

hamza baqqali 15 Reputation points

2023-06-10T16:14:13.79+00:00

the below screenshot was taken on a physical machine with 8 cores, where all cores were at 100% and cpu speed was far ahead from the base 2.2 GHz speed.

i am pretty sure of it, as there was a video encoding going on (x264 with threads=24).

this one illustrates the per core usage.

both show very wrong processxp cpu utilization.

hope this will be fixed very soon.
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Jernej Simončič 11 Reputation points

2022-11-25T21:11:39.05+00:00

Task Manager lies about CPU usage – it scales it according to CPU throttling, meaning that if your CPU's nominal speed is 4 GHz, and it's currently throttled to 2 GHz while all cores are fully utilised, Task Manager will show 50% CPU usage, while Process Explorer will show 100% CPU usage.
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杨岑 171 Reputation points

2022-12-15T11:01:40.537+00:00

I am not sure what that implies. But, it makes the CPU usage graph virtually useless because 99% of the time it shows nothing in system tray icon.

enxi 0 Reputation points

2023-02-19T23:58:40.0866667+00:00

Thank you for pointing out CPU throttling! Is your example backwards? In my case I'm seeing Process Manager showing 10% while Task Manager is showing 100%.

Pavel Melnikov 0 Reputation points

2024-10-10T08:53:29.2666667+00:00

The bug is about Procexp showing much less CPU usage than taskmgr, not the other way around
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Vs Com 5 Reputation points

2023-07-18T14:32:00.0133333+00:00

I made a feedback in the feedback app as Microsoft only acknowledge bugs reported there! Here is the link https://aka.ms/AAlhb61 upvote it so maybe it will get microsoft attention, or made a new one I will be happy to upvote it.
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Kirill Frolov 0 Reputation points

2023-09-22T12:46:24.6533333+00:00

I have made a report

https://aka.ms/AAmshys

Marc 5 Reputation points

2023-12-27T18:57:47.5233333+00:00

Does that feedback https://aka.ms/AAlhb61 still exist? When I try to view it, Feedback Hub opens and says "Your account doesn't have access to this feedback." That's in spite of having used Feedback Hub to report bugs previously.

The report https://aka.ms/AAmshys does open in Feedback Hub for me, but all it contains is a link back to this same page and "We've got it", presumably from Microsoft. Ugh.
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Marc 5 Reputation points

2023-12-27T19:05:10.14+00:00

SysInternals, or Microsoft, whoever actually maintains Process Explorer, please fix this. I used to keep Process Explorer running minimized, with its CPU usage icon in the tray. But on Windows 11 the CPU usage is so badly off that it's useless. Just earlier during a Windows Security scan it showed 11% usage, while Task Manager showed 33%. I basically stopped using it, which is a shame as it was such a nice utility.

There's also the bug where launching it at startup/logon creates a process with no window and no try icon. Either by putting a shortcut in Start menu > Startup, or by checking Process Explorer option "Run at logon". The combination of those two made me stop using it.
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Kirill Frolov 0 Reputation points

2023-12-27T19:15:58.5566667+00:00

What is the version of process explorer?
Try to update it from https://learn.microsoft.com/en-us/sysinternals/downloads/sysinternals-suite

My version is 17.05

Rickard Rosenberg 5 Reputation points

2024-02-26T15:06:48.0066667+00:00

Seems it might be PE that's "correct", they're measureing differently:
https://aaron-margosis.medium.com/task-managers-cpu-numbers-are-all-but-meaningless-2d165b421e43

Brok3n Cogniti0n 20 Reputation points

2024-02-26T15:27:16.83+00:00

No, Process Explorer is not correct. It can be easily tested by running a game where there's shader compilation, which will likely max out many CPUs. How do you know it's maxed out? By tracking power usage and frequency, which do not lie. Meanwhile, just as the CPU is topped at its max TDP, Process Explorer will show 10% utilization or something. I don't understand why is it so hard to fix this, it's quite easy to reproduce.
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虫虫 0 Reputation points

2023-08-30T13:11:58.7333333+00:00

this is my computer.

win11 22h2 CPU—AMD 3600 GPU—NVIDIA GTX1660S

task manager display CPU use age always 99% or 100%.

Process explorer display CPU use age onley 4%-86%.

another compter win10 CPU—intel 10700 GPU—NVIDIA P1000

task manager display CPU use age always 2% when i open many programs.

why?
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