Windows 10 1909 sluggish after ~2 hours use on Word/Excel

First post. I've had an ongoing problem with Windows 10 for the last couple of years. Basically when using a second screen a Dell P2415Q on my laptop I found that the whole system become sluggish after a couple of hours. I assumed it was my Dell XPS 9560, and upgraded the memory, SSD and later the wireless card. Then I switched to my work laptop a Dell XPS 9370 and experienced the same lags.... so I changed monitor to a cheap Lenovo and no change.

As it seemed to be mostly keyboard lag, I ditched my Microsoft Surface keyboard and mouse and used a spare Pi wired keyboard - no change! As a last resort (as both my Dells were reconditioned), I just got a brand new HP Z2 mini G4 workstation with Quadro 1000 graphics (using both the Dell and Lenovo screen).... and it is still the same! So I am coming to the conclusion it is something with Windows 10, and I am fully up to date with patches and drivers etc.

My basic usage example is 2-3 Word documents open, 2-3 Excel documents open, 2-3 Adobe Acrobat Pro 17 documents open and Outlook. Sometimes I have Microsoft edge browser up, but I have noticed that during these sluggish periods it periodically crashes for no reason (this makes me wonder if there is some aggressive power management going on?). I'm on Windows 1909 and Office 365 home and to be honest have not installed much else at all since getting the new workstation.

The symptoms are:

• delay when focusing to a new window
• typing in Excel/Word many seconds delay before focus and then catches up
• edge browser just randomly crashes
• delay when scrolling or using arrow buttons
• closing windows (Word/Excel) delay
• various graphical glitches e.g. Outlook folder list is just grey and after many seconds the text shows up one line at a time (slowly)
• notifications do not come up when clicking taskbar icon
• get to point where clicking in cell does nothing in excel, then only a reboot will fix...

So, when I am away at work I am using some prehistoric Dell OptiPlex with absolutely no issues whatsoever. So this makes me wonder if it has something to do with OneDrive? I have tried to fully remove this, unlinked first then uninstalled but even after group policy edit it still lingers (on reboot the user/onedrive folder is back...)

It feels like a memory leak, but when I go to task manager there is plenty available and not any huge resource hogger. I'm at a loss now, and as has been said have seen this on multiple computers and changed just about everything hardware wise. That said, I have not resorted to running windows for best performance... because its an i7-9700 with Quadro card, so overkill for basic office tasks.

If someone can advise how to set up a log (or software to log) so that I can try and pin down what this is it would be much appreciated. I will endeavour to get some video grabs as well.

Normally those delays are due to a hard work on the background. It can be the antivirus scanning the computer, the WU preparing an upgrade etc
Open Windows Task Manager (Ctrl+Shift+Esc) - Performance tab - Resource monitor

Yeah had task manager up, nothing really leaping out. Memory use around 30% and CPU around 20%. Its fully up to date, no updater task etc.

What process is using 20% CPU?
Mine is less than 2%.
Do you have Cortana enabled?

No single one, just everything adding up to that. Yes, Cortana is running. That's a good call I hadn't thought of that. Will turn it off also.

since you seem to have all these problems mostly in Office programs, I would try reinstalling Office first.

On both the laptops and now the workstation it's been a clean office install. That said, I think on the workstation it defaulted to a 32bit install so could uninstall and try the 64bit. I have seen graphics glitches in other programs, but yes mainly office.

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I just installed stardock start10 menu and removed cortana via group policy.... hopefully the latter might improve things

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I also went in and disable background running apps. To be honest what I have done has made it worse I feel as it was getting laggy after a couple of hours, and now it is laggy pretty much straight away after a reboot... I was looking last night at NTlite and wondering about building a stripped version of Win10 to test.....

Have a look What programs / apps to use to tweak Win 10

I dont think it is a resource issue because of hardware limitations. It could be a driver issue related to the Quadro though...

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"stripped version of Win10 to test....."

You are gonna have problems later on and you are not gonna know why.... It might be isnteresting as a quick test. But not to use it as a definitive system.

Yeah I agree, it would mostly just be for a test and to satisfy my curiosity... That said I just installed 32GB ram today and it seems to be very sprightly now (and so it should be).....

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Installed NOD32 last night going down a different avenue to see if it was A/V... no change. One constant that I have seen is that when things get really slow the notification or 'Action Centre' fails to come up when clicking on the taskbar icon. This is the only thing that I can replicate every time...