Why does DWM.EXE use so much memory?
DWM.EXE is the Desktop Window Manager in Windows Vista.
When you’re using Aero Glass in Vista, DWM owns an offscreen bitmap for every open window, the size of the window, with a rendering of that window’s contents.
DWM needs this so it can quickly show you thumbnails of all the open windows, and so it can do things like composing and animating quickly. But it requires a lot of memory.
On my system, for example, opening a single full-screen Notepad window causes DWM.EXE to allocate an additional 4.8mb of memory.
Close Notepad and DWM gives this memory back.
I opened a hundred Notepad windows to test, and yep, it allocated almost half a gig of RAM for the bitmaps.
If you can’t afford this much RAM, don’t use the Aero Glass theme in Vista.
February 10th, 2007 at 12:31 pm
Yup…requires memory for Vista to look pretty. A cheaper alternative to purchasing RAM is to buy a 1 or 2gb USB 2.0 flashdrive and use Vista’s ReadyBoost (uses usb stick as RAM)
February 14th, 2007 at 5:46 am
Good explaination as to why DWM takes up so much ram.. But not using Aero is really the answer I was looking for…. Have you found any other options???
February 15th, 2007 at 7:27 pm
Get a comp with specs like mine.
MOBO: Asus M2N32Sli Deluxe wireless edition
CPU: Authentic AMD64bit 4600+
RAM: 2x 1gb OCZ VX2 DDR2 PC2-8000
VIDEO: NVIDIA 7950GX2 1MB DDR3
HD: Dual 250 Maxtor Hard-Drives in a stripe raid
CASE: NZXT Nemesis 660W power
and then it won’t cause you anymore problems.
February 19th, 2007 at 6:56 pm
Thanks for the explanation.
I was more concerned with the CPU cycles the dwm process is taking than I was the RAM.
February 21st, 2007 at 7:39 am
Very helpful; can’t imagine anyone would consider the glass pane view worthy of so much in the way of processing resources. Any other tips for improving efficiency of Vista? I have a mamma jamma processor but, frequently, the simplest tasks seem to stall.
May 5th, 2007 at 2:55 am
Hmm, I only have Vista Basic, which doesnt come with Aero… so why do I still have dwm.exe? And should I just disable it since its only for Aero?
May 30th, 2007 at 4:39 pm
I guess I agree with Mike. If it’s too much resources, turn it off. If you have the equipment to crunch this stuff…. it works well and I don’t see much slow down. I’m an IT guy and long time Micro$oft hater… but vista is one of the best OS’s I’ve ever used. After a service pack or two… it should be awesome. I do get a little wigged out by the DRM features… oh well.
June 3rd, 2007 at 7:49 pm
Great tip!
I just turned off all the visual effects. That makes it much easier to navigate too.
June 29th, 2007 at 5:30 pm
How do I disable the visual effects?On Vista home permium?
July 29th, 2007 at 11:17 pm
I have a laptop with Vista and the dwm is causing a black screen of death – I can’t seem to find a fix. Any ideas?
August 8th, 2007 at 8:27 am
look guys its easy go windows clasic theme buy ram or go back to xp
using usb flash drive as spare ram is pointless random acess memory thats 8 IC’s being accesed simultaneously not half of one stuck in a flas drive also limit the number of icons on ya desktop all images need to be renderd mail me if ya need help kwith any thing else this stupid maddogthefirst@hotmail.com
August 16th, 2007 at 6:03 pm
“Mike Says:
February 15th, 2007 at 7:27 pm
Get a comp with specs like mine.
MOBO: Asus M2N32Sli Deluxe wireless edition
CPU: Authentic AMD64bit 4600+
RAM: 2x 1gb OCZ VX2 DDR2 PC2-8000
VIDEO: NVIDIA 7950GX2 1MB DDR3
HD: Dual 250 Maxtor Hard-Drives in a stripe raid
CASE: NZXT Nemesis 660W power
and then it won’t cause you anymore problems.”
Mate.
Why would I want to down grade my system? LOL
November 24th, 2007 at 12:24 am
You know, everytime they get the MS Windows operating system up to speed and get most of the bugs out, they completly rework it and start over. First there was Win3.1, then you installed 95 and your computer slowed to a crawl. They never really secured 95 and moved onto 98 then it slowed to crawl again.
About the time they got XP fixed, I purchase a new laptop with Vista. Now, (even with 2 gigs of ram) my Vista is actually slower than my first notebook which was an IBM Thinkpad 486 running windows 3.1! So, I kill all visual affects and kill aero. Now my computer ugly but it works.
I don’t know when XP will die, perhaps 2 more years even, but I would not recommend anyone purchasing a new computer with Vista. There is just too many tools I use that doesn’t work with Vista. Sometimes I have to borrow my wife’s XP box and that just pisses her off;)
November 27th, 2007 at 9:24 am
Leave on the Aero features, but if you plan on running memory or cpu intesive software like graphic design software, or 3D games, simply right click on the .exe or the shortcut of the program where you require every bit of cpu power and ram and, under the compatibility tab, tick the box that says “Disable desktop composition”. This will disable all aero features temporarily whilst that program is running. Most games for example run in full screen anyway by default these days, so you can’t even see the aero window! However, if you’re just using MSWord or something it’ll still be there for you looking all nice and pretty
(Also, this remove graphical and colour corruptinos in older games as well such as Fallout 2 and Theme Hospital for example, that only support 16bit mode)
Easy Peasy
December 15th, 2007 at 6:02 am
Mat, that’s a great tip! Thanks! You’re the greatest!
December 26th, 2007 at 10:08 am
I have a dual head Nvidia 8800 with 256MB of vram, 3GB of RAM, intel quad core 2.66mhz processor, and vista aero still slows down lots of programs, particularly the redraw speed. The amazing thing is, my crappy little mac mini with a power pc (2 years old) supports all the fancy interface features in Leopard, including most of what Aero offers. The power alone drawn by Aero on all the computers probably puts many thousands of tons of C02 into the athmosphere thanks to bloated, crummy programming. Shame on Micro$oft for such shoddy workmanship.
December 30th, 2007 at 12:27 am
I have a Vista based machine with 4GB of ram – Q6600, 8800GTS (640MB) and aero runs fine on my system…. nothing is slow. The reason your mac mini supports the “fancy features” is because its a Mac! By that I mean that it doesnt require any processing power because you cant even do a fraction of the things you can do with your PC. Have fun with itunes and entourage! I am off to play Crysis!
January 15th, 2008 at 11:22 pm
I know I’m a little late here, but I’ve disabled dwm.exe following these instructions:
http://thevistaforums.com/index.php?showtopic=12540
I don’t know if doing this is the same as turning off Aero, but the only visual difference I notice is that the windows are no longer transparent. They’re still kinda silvery-looking (far from ugly) and alot of my ram has been freed up.
Again, I know I’m late here, but I though I’d share in case someone new to the vista game came accross this post (like I did) when looking for a way to speed things up.
January 31st, 2008 at 7:07 pm
Yea Quad Core alone makes up for all the difference. It is like all other changes over to a new technology or change in any form. I remember the headlines of Computer Shopper saying Intel 486/66 too fast for consumer use, the platform what surely be for business only. ha ha
February 4th, 2008 at 8:58 pm
Jay – I agree. I would love to have even XP back (choke!)
Mat – thanks! I am doing pretty intensive 3D work, and when I did your trick my dwm.exe went from 52mb to 2.
BTW – I have a quad core with 4gb of ram. But I was planning on using it for something other than a crappy operating system.
February 26th, 2008 at 9:47 pm
Mat- that is the best advise I have heard! I am not lacking in the cpu or ram but I am old win98 man so I like to have every ounce I can squeze out of my ‘puter.
September 15th, 2008 at 10:39 am
Use Linux or Mac OS can solve this problem…
November 16th, 2008 at 1:14 am
Wesley-
“Wesley Says:
September 15th, 2008 at 10:39 am
Use Linux or Mac OS can solve this problem… “
November 16th, 2008 at 1:15 am
AWESOME IDEA!! I TRIED UBUNTU BUT ONLY PROBLEM IS GETTOIG THOSE NIMEROUS PLUG-INS AND STUFF
November 18th, 2008 at 5:41 pm
With how cheap RAM is, who really cares how much it’s using. I’d be more worried about the CPU usage. Considering basically everyone pins CPU usage at 100% on very regular basis, Desktop Window Manager is driving you that much closer to max throttle.
November 18th, 2008 at 5:42 pm
Oh and >>>Wesley…
As soon as Fallout 3 is available for Linux, maybe i’ll consider switching
September 8th, 2009 at 10:17 am
Little late to the game. Was wondering what dwm.exe was and why it needed 1.7GB RAM. I think it may have a bug in w7 rc1 7100.