DisplayFusion RSS: dwm.exe (aero) massive slowdown/CPU increase when using DF to change monitor profiles https://www.displayfusion.com/Discussions/RSS/?TopicID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5 DisplayFusion RSS: dwm.exe (aero) massive slowdown/CPU increase when using DF to change monitor profiles Tue, 05 May 2026 23:38:06 GMT en hourly 1 https://www.displayfusion.com/Discussions/RSS/?TopicID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5 RE: dwm.exe (aero) massive slowdown/CPU increase when using DF to change monitor profiles https://www.displayfusion.com/Discussions/View/dwmexe-aero-massive-slowdowncpu-increase-when-using-df-to-change-monitor-profiles/?ID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5#3 Tue, 04 Apr 2017 16:34:29 GMT Binary Fortress Software https://www.displayfusion.com/Discussions/View/dwmexe-aero-massive-slowdowncpu-increase-when-using-df-to-change-monitor-profiles/?ID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5#3 DisplayFusion Strange! Could you attach a copy of your troubleshooting info? I'll just have a quick look to see if I can spot anything obviously wrong.
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Thanks! ]]> RE: dwm.exe (aero) massive slowdown/CPU increase when using DF to change monitor profiles https://www.displayfusion.com/Discussions/View/dwmexe-aero-massive-slowdowncpu-increase-when-using-df-to-change-monitor-profiles/?ID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5#2 Mon, 03 Apr 2017 01:07:16 GMT Binary Fortress Software https://www.displayfusion.com/Discussions/View/dwmexe-aero-massive-slowdowncpu-increase-when-using-df-to-change-monitor-profiles/?ID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5#2 DisplayFusion Well, nevermind. It started happening again even though I didn't change video modes. Not sure what is going on. ]]> dwm.exe (aero) massive slowdown/CPU increase when using DF to change monitor profiles https://www.displayfusion.com/Discussions/View/dwmexe-aero-massive-slowdowncpu-increase-when-using-df-to-change-monitor-profiles/?ID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5 Sun, 02 Apr 2017 01:24:03 GMT Binary Fortress Software https://www.displayfusion.com/Discussions/View/dwmexe-aero-massive-slowdowncpu-increase-when-using-df-to-change-monitor-profiles/?ID=a61fb6a8-7960-4e2a-b2c6-96fdd44464f5 DisplayFusion So, this seems to only be an issue with newer builds of DisplayFusion, because I've been using the product for over a year now and this just started happening.

Long shory short: if I switch from one monitor profile to another, dwm.exe starts using massive amounts of CPU, Aero effects grind to a halt, and Windows detects the problem and offers to turn off desktop composition. The only way I can get smooth aero effects back at this point is to reboot the system.

Here is the funny thing: if I use Windows Display Properties to change from one to two monitors, the slowdown effect does not happen. It ONLY happens if I use DisplayFusion to adjust the monitor profile-- using regular old Windows to enable the second/third/forth monitor does NOT cause the dwm.exe slowdown. ]]>