I think I may have the problem licked now. The solution to the problem is in the latest generic graphics driver from Intel, 30.0.101.1191. This is now an official release and includes the fix to the memory leak problems and instability in Dell's current driver, 27.20.100.9664. It's very important that the Dell OEM driver stay installed on the system and the new driver installed "over" it, as per this notice from Intel. Both drivers must be present in the system's Driver Store; otherwise Windows Update will try to revert the driver back to the OEM driver. Of course, use Device Manager to ensure the new driver is the active one. That's what I tried to do on my system initially (before reinstalling Windows), but I couldn't get the new driver reliably installed. I suspect the Driver Store somehow got corrupted, perhaps when I was using Driver Manager to try and uninstall drivers. Maybe the version of the driver that Windows loads in the background during installation was causing a problem (I eliminated that this time around). Reinstalling Windows and keeping it simple (OEM driver, then generic driver) seems to have done the trick. I need to mention that Intel warns against using their generic drivers long-term. OEM drivers like Dell's have customizations and performance tweaks specifically for their hardware, and ideally, users should be running the OEM drivers. I sincerely hope Dell will soon release their own version of the driver that includes the DWM fix (i.e. one labeled 30.0.101.1191 or newer), and when they do, I will use that instead. So far, I have noticed no ill effects using the generic driver, and my system seems to finally be stable. I wish Dell had been more help (actually, any help) with this issue, which I've been wrestling with for two months on a brand new system. Dell users with complicated/intermittent problems will have better luck searching the internet for clues than consulting Dell support.
This could potentially also go in the Windows 11 forum, or in the Support forum, but I’m hoping to hear from other users as well– find out who might be experiencing something similar and/or alert them that this might happen to them. My new Vostro 5890 (Intel UHD Graphics 630, Windows 11) about once a day or more while in use, starts page thrashing and becomes unresponsive; if I don’t catch the problem in time (which is often, since it’s silent), it must be shut down hard and rebooted. The problem is a memory leak in Desktop Window Manager (dwm.exe). I don’t have to be doing anything more than browsing pages with Firefox, and suddenly DWM will start ballooning. I can’t figure out what kicks it off, but once it starts growing, it seems to grow exponentially – starting at 50-100 MB, it quickly consumes several gigabytes and the system starts page thrashing and stops responding. At worst, during one event (according to Event Viewer) Windows’ Resource Exhaustion Detector reported DWM consuming 25 GB of virtual memory (the system has 16GB of RAM). If I keep Task Manager open and watch DWM, I can sometimes catch the problem while it’s relatively small. Logging out causes DWM to exit normally. If I kill the DWM process from Task Manager, it usually just restarts without problems, though sometimes there are other problems down the line (e.g. explorer.exe hanging). The problem never seems to happen while the screen is locked; I can leave it locked for hours at a time without worry. Using the graphical desktop seems to be a prerequisite. I can’t take my eyes off Task Manager lest DWM get out of control. Windows users have complained about DWM memory leaks (sometimes specifically associated with Intel integrated graphics) since at least Windows 10 in 2020. Most of these anecdotes end with upgrading to the latest graphics drivers. I am up to date on drivers and firmware as far as I can tell from SupportAssist, Windows Update etc.but the problem persists. So far I’ve made three calls to tech support so far about this issue. Call #1 October 27, several days after I took delivery of the system. The system had been shipped from the factory with Windows 10 installed (20H1, I think), but I had immediately performed an upgrade to Windows 11 via Windows Update. When I spoke to the tech, I related that some folks on the net reported a DWM memory leak that started in WIndows 10 and survived an update to Windows 11; in those cases, installing Windows 11 from scratch reportedly cleared up the problem. The Dell tech agreed, so he stayed on the phone while I created Windows 11 install media, wiped the SSD and installed Windows 11. He then via RemoteAssist installed the latest drivers and Dell software. This unfortunately did not clear up the problem. I’m not sure why I didn’t notice the problem (much?) during most of November, but during that time I expanded the RAM in the system from 8GB to 16GB, adding another of the same Samsung 8GB DIMM that was already in the system. Toward the end of November the problem came back with a vengeance.  Call #2 was December 1. The tech noticed that the BIOS was out of date (SupportAssist's automatic check hadn't found it). He stayed on the line while I manually downloaded and updated the BIOS. The problem soon recurred, however. In between calls 2 and 3, I installed Intel's latest driver for UHD Graphics, using Intel Driver & Support Assistant. This updated the driver version from 27.20.100.9664 (Dell's latest) to 30.0.101.1069 (Intel's latest). The problem recurred that evening, however. Call #3 was December 7. The tech fundamentally didn't understand the problem, or I didn't explain it well enough. Even though I described a memory leak problem, he focused on what he thought were potential hard drive issues. In a RemoteAssist session he disabled the SysMain and Windows Search services, performed a Disk Cleanup on my C: drive (SSD), re-installed the Dell version of the UHD Graphics driver (27.20.100.9664), and installed a new system BIOS that had just been released on 12/6. He then declared my issue resolved, and told me Dell support would call me the next day (12/8) between 10 am and noon to check on me.  When I mentioned the disabled services, he told me in a reassuring (condescending?) tone that the reboot we’d just performed had automatically restarted them. After our call, II had to manually restart both services and re-enable search indexing on the system. I figured we had at least updated the BIOS, so maybe it would have an effect; the problem persisted however. Dell support never called back on 12/8 either. Meanwhile, I’ve been troubleshooting the problem by eliminating settings and background actions that potentially might be contributing to it. I’m running out of things to turn off. It’s been suggested that I downgrade to Windows 10; I really don’t want to do that. I like Windows 11, and I don’t want to live in fear of upgrading to 11 if I don’t know the problem has been fixed. If this is a Windows/Intel bug, I’d rather it get reported and worked on than ignored. II think my settings are pretty vanilla.  imagine there’s something I’m running or doing that initiates the problem, but it’s nothing “illegal,” nothing I shouldn’t be doing on Windows. I can turn off some user interface fluff like transparency settings, but I’d like some guidance and some tracking. I don’t mind working the problem, but I’d like some backup here. I mean, I have a one-hour Zoom call to be on tomorrow, and I can’t use this computer because there’s a good chance it’ll go belly-up during that time. That’s unacceptable.   Thanks for listening.
Vostro 5890/Intel UHD Graphics/Windows 11: Desktop Window Manager (dwm.exe) 
memory leak