Get better Game Performance under Vista by disabling DWM on a per-application basis!

[Black Panther]

I just came across this tip/tweak, which probably many who are familiar with Vista already know... It's about disabling the aero effect on a per-application basis, so that you get vista basic interface during gameplay (when you're not going to see it) and it switches back to aero when you exit the game.

DWM, or the Desktop Window Manager, turns the graphics card into a shared resource which allows for the Aeroglass effects and the tear-free desktop. When running normal applications, this is a good thing because it offloads the graphics work (the bulk of which was handled by the CPU in Windows XP) to the GPU, which, when running normal applications is sitting in your computer doing nothing. With Aeroglass/DWM on, the CPU is freed up for other duties as all of the desktop graphics are now handled by the GPU.

In DirectX 9 and OpenGL games however, having Aeroglass/DWM on can decrease performance. This is for a number of reasons :
1.DWM makes the video card a shared resource. When DWM is on, programs are not allowed direct access to the video card.
2.DWM uses both System RAM and VRAM because it maintains an offscreen buffer for every window.

Fortunately, Microsoft has provided a way to disable DWM on a per-application basis so you can still enjoy Aeroglass when not running games. To disable DWM on a per-application basis, right click on the application/game's icon and select properties. Navigate to the compatibility tab, then find and check Disable Desktop Compositing. Now, whenever you launch that program, Windows Vista will temporarily switch back to the Windows XP style graphics subsystem.

DirectX 10 games shouldn't be affected as much (if at all) by having DWM on because the DirectX 10 API is designed around having the GPU as a shared resource and is better able to handle GPU multitasking.

With a few simple steps, on most setups, you can easily make your games run as fast or faster than in Windows XP under Windows Vista.

This will work on both the 32-bit and 64-bit versions of Windows Vista.

 

[alexp999]

Vista disables aero glass when you go into a game anyway. At least it does for me, I dont have to do any tweaking or changing of settings. You often see it just as the game launches. If the game has a launcher window, you see the theme change on it to standard aero, just before the game launches into full screen.

 

[Black Panther]

you see the theme change on it to standard aero, just before the game launches into full screen.

Apparently this tweak changes it to vista basic, not even standard aero.

I get a brief popup on lower right of monitor when this happens, I cannot remember what it says right now since I'm not on the laptop...

Also, if you open the task manager in the middle of a game, without this tweak you'll still see the DWM process running.

I think to properly check whether this works or not one must run a benchmark with and without the tweak... for example the Crysis benchmark in DX9, or 3dmark06.

 

[EviLZeD]

Vista disables aero glass when you go into a game anyway. At least it does for me, I dont have to do any tweaking or changing of settings. You often see it just as the game launches. If the game has a launcher window, you see the theme change on it to standard aero, just before the game launches into full screen.

It does similar thing for me too before the games just about to launch the glass effects for aero and other effects change but the skins the same like home basic.

 

[Champ]

For all the resources it takes, it should shut itself off.

 

[wolf2009]

For all the resources it takes, it should shut itself off.

It does for me too, as is does for others

 

[qamulek]

Eureka

hmmm so this aero stuff might be what randomly makes Oblivion try to switch back and forth to the desktop resulting in an ugly flicker in the right corner :OOOO

OH! also whenever I launch TF2 I alwasy get the dialog box with the "please contine I want to play my game" button, but then when TF2 launches windows goes into a loop switching between TF2 and the desktop. The only way to stop the loop before it happens is to click on the TF2 startup screen then hit enter to skip the videos. HEY! just tried this with TF2, and it stopped the loop problem

 

[Deleted member 38767]

Every time when you start game (and maybe every fullscreen app, I'm not sure) in Vista the OS switch to Visa basic. If you Alt+Tab while playing the Aero comes back while the game is minimize and turns off again when you go back to gaming. Switching off the DWM may help performance as there are less processes running but that's all.