Anyone else getting high DWM CPU usage when the screen is off?

mikeymikec

Lifer
May 19, 2011
21,067
16,301
136
I'm using: R9 380X graphics card (16.5.1 driver), Win7 patched up-to-date.

I haven't observed the problem the whole time I've owned this card (a few months), but unless I notice the CPU fan making slightly more of a noise than usual or unless I notice Process Explorer's CPU graph on the systray showing excess CPU when I come back to my PC, it's not that obvious a thing to spot.

Of course I'm also assuming that it's graphics related, but I've read up a bit already and other people seem to have problems with particular apps running in the background whereas I don't (ie. the problem occurs when nothing else is running), nothing has changed in months except for the card (with a string of rapid graphics driver updates in that time).

If the problem occurs, then IIRC it will keep occurring every time the screen goes off until I reboot or power cycle the machine. No other immediate symptoms apart from higher CPU usage (between 25-50% of i5-4690k, used by dwm).

I have a theory that the problem only occurs during a Windows session where I've had to forcibly close 'The Witcher 3', the symptom of which is that the game freezes momentarily, then I get dumped back to the desktop and there's a box on the taskbar showing the game still running (along with the music theme at the time that the game stopped), then I open up Process Explorer and terminate the game there (I can't alt-tab back in or anything like that). I can then restart the game. Also, when this game problem occurs (about once a week on average currently, I play it for a while pretty much every day), a graphics driver reset is logged.
 
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JeffMD

Platinum Member
Feb 15, 2002
2,026
19
81
I have found that in screen off state, windows finds it a prime time to download and update windows updates.
 

mikeymikec

Lifer
May 19, 2011
21,067
16,301
136
I have found that in screen off state, windows finds it a prime time to download and update windows updates.

This isn't something that dwm.exe does, it stands for Desktop Window Manager. It handles desktop composition (in Win7's case, Aero).

Windows update is handled by one of the many instances of svchost.exe.
 

Ketchup

Elite Member
Sep 1, 2002
14,559
248
106
I have read the antivirus programs do this. I haven't seen anybody list which ones do/ don't do this, but you might try an uninstall and see if that changes.
 

TeknoBug

Platinum Member
Oct 2, 2013
2,084
31
91
"update or scan when computer is idle" falls under this, I've seen that option in some programs so this might be it.
 

BonzaiDuck

Lifer
Jun 30, 2004
16,655
2,034
126
Among other things, look into a freeware/shareware program called "Latency Monitor." It may give you some clue about conflicting drivers which also cause high CPU usage.

But from the OP's last post, it may be a problem with the game he's playing.
 

TheRyuu

Diamond Member
Dec 3, 2005
5,479
14
81
I have a theory that the problem only occurs during a Windows session where I've had to forcibly close 'The Witcher 3', the symptom of which is that the game freezes momentarily, then I get dumped back to the desktop and there's a box on the taskbar showing the game still running (along with the music theme at the time that the game stopped), then I open up Process Explorer and terminate the game there (I can't alt-tab back in or anything like that). I can then restart the game. Also, when this game problem occurs (about once a week on average currently, I play it for a while pretty much every day), a graphics driver reset is logged.

Do you play in Fullscreen or Borderless Windowed?
 

TheRyuu

Diamond Member
Dec 3, 2005
5,479
14
81
Fullscreen.

Have you tried it with borderless? I realize there will likely be a performance penalty although it shouldn't be too severe. It may not be the answer you're looking for but if it's a recurring issue it may be worth a shot in the short term until a better solution could be found.