[Windows update installing the new Edge browser] Update KB4559309 Makes Computer Unbearably Slow

@LadyWho - As you are using the "Update KB4559309 Makes Computer Unbearably Slow" thread, I must assume you are using Windows 10 devices. If so, please post and confirm, and post the actual version (version and OS Build info from running the "winver" command). To do that, right-click the start menu icon, choose Run, key in winver and click on OK. Device makes/models, memory capacity would also be useful.

Secondly, you do not state what the "cleanup a weekly" is that is taking 25 minutes, more detail would be useful!

It may be that you are running an under-powered machine (weak CPU, not enough RAM installed for the tasks being done), with a very little free space on our hard disk, or that lots of unnecessary startup programs are running at boot, extra "scanning" stuff (e.g. McAfee), more than one anti-virus active etc, so the update to the new edge failed to complete the favourites import (or the import script timed out).

All those above are just assumptions of course, as you have posted no details to work with to provide any constructive help.

If your problem is limited ONLY to EDGE performing badly, try downloading the latest Firefox browser, import any web account passwords and favourites from EDGE, and try that to see if it is better. I find it has a very good, useful built-in password manager. It also has its own "private" DNS if you want to enable it (it is called DoH - DNS over HTTPS - it used Cloudflare as the default if you want to activate it).

If the issue still occurs there, then your issue is more system (OS) software related, resource related (lack of free memory, low free space on disk, weak CPU), or hardware (CPU power throttling due to overheating caused by clogged or failing fans/heatsinks), or slow network issues (weak WiFi - too far from router). When was the last time you rebooted our router?

To narrow things down, check your disk free space, use the Task Manager to check CPU hogging/high activity, along with memory and disk activity. Download and use "speccy" from Piriform, to check your CPU temperature and speeds (it will show up throttling when the frequency multiplier drops from say 30 to 8). Speccy will also show what memory hardware you have (so you can plan to upgrade it if you need to).

Similar issue. After installing this update (on windows 2004) office products suddenly use up 25-40% of the CPU. I'm only a few hours in after doing this update so who knows what else I will find. No way to uninstall unless doing a complete restore, which also involves complete uninstall of my copy of Bit Defender. Thank you Microsoft for wasting my time again.

Update: Before I went ahead and did a system restore I decided to see if there were any updated drivers for my laptop, which is a Dell Latitude 7490. There weren't. Then I tried disabling BitLocker and everything went back to normal. No more excessive CPU usage or poor performance. As Paul said he solved the problem by reinstalling the motherboard drivers. Were those new drivers or the same as previously, just reinstalled? Now I am also curious, does anyone else with issues have BitLocker enabled?

had the exact same issues at the end of my using win 10 1909 and after the first updates to windows 10 2004. only thing that really solved it for me was getting the windows 10 2004 .iso and performing a repair install while  not connected to the internet which gave me windows 10 2004 build 19041.0. after that I installed the latest updates, and after installing / uninstalling the update before letting it install a final time, it fixed the issue. the update itself seems to be very temperamental. it seems to botch something during the update process about 50% of the time (roughly) the rest of the time, it installs correctly and everything works as it should. 

the main reason for the repair/inplace upgrade of win10 2004 is to get rid of the problematic update by force. and you should end up with a smooth running OS. It's the updates after that that can be a pain in the ****