Serious Discussion Windows 11 23H2 upgrade causing performance loss and trusty Microsoft Defender may be why

[CyberTech]

This weekend we published a feature looking at the performance improvements, or regressions, one can expect if they were to move from a clean-installed Windows 10 22H2 system to a clean-installed Windows 11 23H2 PC (similar to the one where we upgraded to Windows 11 22H2). What we generally noticed was that the differentials were typically within the margin of error or in the imperceptible zone, though there were situations where one was quite a beat ahead of the other.

Although we haven't yet published our findings showing the differences between Windows 11 22H2 and 23H2 (we plan to do it soon), several users on the internet say they are suffering from performance losses after upgrading to version 23H2.

Reddit user BNSoul opened a thread on the Windows 11 subreddit explaining how they noticed performance regression of around 5 to 8% in several CPU benchmarks. Games also apparently exhibited random stuttering and hitching. They write:

To put it simple[sic], every CPU benchmark shows significantly reduced CPU performance after updating to Windows 11 23H2 from 22H2, even after a fresh/clean install.
...
I could add an endless list of benchmark results here but just lets say it's always 23H2 5-8% slower in every single one be it single or multi-thread compared to 22H2.
Games are also affected with random stuttering, all of this fixed by rolling back to 22H2.

Full article

Windows 11 23H2 upgrade causing performance loss and trusty Microsoft Defender may be why

Windows 11 version 23H2, much like some of the previous feature updates for Windows 11, is apparently causing performance loss, and it could have something to do with Microsoft Defender.

www.neowin.net

 

[Gandalf_The_Grey]

Interesting comment in that article:

Received an answer from Microsoft after 3 days, they told me to reset Windows Defender through a couple of PowerShell commands

(1- "Set-ExecutionPolicy Unrestricted" and

2- "Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage") then reboot and enable CPU Virtualization in BIOS (SVM in my X570 BIOS),

then in Windows 23H2 open Windows Security and enable Memory Integrity under the Core Isolation settings. Restart and Hypervisor should be running, Virtualization Security will be Enabled and... that fixes the CPU performance issues, CPU now performing as in 22H2 where I had these security features disabled.