Testing out an idea. Putting DWM(manages the mouse, keyboard, etc.) into the foreground with regedit

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davidl41
Posts: 12
Joined: 08 Dec 2025, 15:42

Testing out an idea. Putting DWM(manages the mouse, keyboard, etc.) into the foreground with regedit

Post by davidl41 » 26 Apr 2026, 10:14

In regedit, I changed DWM(manages the mouse, keyboard, and so on)to be in the foreground rather than the background. To benefit from more CPU priority in the same way the game does. I think I can feel a difference in mouse responsiveness, and DWM.exe shows in Presentmon, which I think means that DWM.exe is in the foreground. The general idea is that putting DWM in the foreground for more CPU priority is beneficial to input lag in some way.

Hoping for someone that knows more about DWM and Win32PriorirtySeparation to shed some light on what might be happening with those regedits! If anything.

Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\PriorityControl
I set "Win32PrioritySeparation" to 22 decimal.

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Multimedia\SystemProfile\Tasks\Window Manager
I set "Background Only" to "False".

Hyote
Posts: 677
Joined: 09 Jan 2024, 18:08

Re: Testing out an idea. Putting DWM(manages the mouse, keyboard, etc.) into the foreground with regedit

Post by Hyote » 26 Apr 2026, 18:25

I think these two changes are imperceptible from a latency standpoint. I had more success modifying DWM threads that are connected to input and rendering and disabling unneeded ones. Some people swear by decimal 22 or 24 (Windows Server 2022) for Win32PS but for latency, 36 or the default 38 is better.

davidl41
Posts: 12
Joined: 08 Dec 2025, 15:42

Re: Testing out an idea. Putting DWM(manages the mouse, keyboard, etc.) into the foreground with regedit

Post by davidl41 » 26 Apr 2026, 21:03

Hyote wrote: ↑
26 Apr 2026, 18:25
I think these two changes are imperceptible from a latency standpoint. I had more success modifying DWM threads that are connected to input and rendering and disabling unneeded ones. Some people swear by decimal 22 or 24 (Windows Server 2022) for Win32PS but for latency, 36 or the default 38 is better.
The idea is to put DWM to the foreground as a foreground app rather than it's default state as a background app. As a foreground app it gets 3:1 CPU priority rather than 1:3 CPU priority in the background. When used with 22 or 38 win32priorityseparation.

The situation is seemingly different for latency with that setup. DWM is no longer in the background. It is in the foreground with the game. With 22 decimal it seemingly doesn't have to switch as much because DWM is in the foreground alongside the game. That is the theory. It seems a lot more responsive with DWM in the foreground, and 22 win32priorityseparation in this specific situation seems better.

DWM.exe in the foreground I am more certain of as it definitely feels more responsive. Decimal 22 seems like it should be better when both game and DWM.exe are in the foreground. But, I am not sure how to measure it.

Lurker
Posts: 2
Joined: 31 Mar 2026, 04:52

Re: Testing out an idea. Putting DWM(manages the mouse, keyboard, etc.) into the foreground with regedit

Post by Lurker » 28 Apr 2026, 00:14

Hyote wrote: ↑
26 Apr 2026, 18:25
I think these two changes are imperceptible from a latency standpoint. I had more success modifying DWM threads that are connected to input and rendering and disabling unneeded ones. Some people swear by decimal 22 or 24 (Windows Server 2022) for Win32PS but for latency, 36 or the default 38 is better.
What should i use on windows 11? 36 or 38 decimal/hexadecimal?

Hyote
Posts: 677
Joined: 09 Jan 2024, 18:08

Re: Testing out an idea. Putting DWM(manages the mouse, keyboard, etc.) into the foreground with regedit

Post by Hyote » 28 Apr 2026, 11:27

Lurker wrote: ↑
28 Apr 2026, 00:14
Hyote wrote: ↑
26 Apr 2026, 18:25
I think these two changes are imperceptible from a latency standpoint. I had more success modifying DWM threads that are connected to input and rendering and disabling unneeded ones. Some people swear by decimal 22 or 24 (Windows Server 2022) for Win32PS but for latency, 36 or the default 38 is better.
What should i use on windows 11? 36 or 38 decimal/hexadecimal?
36 decimal on 24H2 and above.

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