Unexplained hard disk activity slowing PC to snail's pace

I have a major problem with my 2½ year old DELL XPS 27 (7760 AIO) PC operating on Windows 10 Home version 20H2. This issue has only manifest itself in the last 6 months or so.
At frequent intervals, if I listen carefully, I can hear frantic activity on the hard drive, for no apparent reason. This slows down the PC’s response time to every command I make – e.g. opening a new programme may take anything up to 5 minutes and the PC may take 1-2 minutes to respond to any keyboard or mouse actions.
I have a support contract with Microsoft and they have helped me to re-install Windows a couple of times, but after only a short while the problem returns. I’ve also enlisted Norton’s help, thinking it might be a virus-checking issue, but to no avail. I’ve downloaded DELL’s programme to run a thorough check on every component in the PC, but this merely confirms that everything is functioning 100%. And I’ve checked Disk Activity and this reveals nothing significant. NB: I do not back-up to the Cloud, so that’s not the cause.
Any suggestions for resolving this problem would be most welcome.

Hey, have a look at dissabling Superfetch.

Uninstall Norton antivirus to see issue resolves.

Completely Uninstall Norton software using:

• 
  NRnR.exe

Instructions

1. Please download and save NRnR.exeto your desktop.
2. Close all programs and double click on the tool.
3. Follow the on-screen instructions.
4. Restart the computer if asked.
5. Then delete the NRnR.exe tool from your desktop.
6. Open the Program Files folder on your local disk ( normally C: )
7. Find and delete the following folders (if present):
   
   
   • Norton AntiVirus
   • Norton Internet Security
   • Norton SystemWorks
   • Norton Personal Firewall
   
   

Thanks 'TidySean'. I've disabled Sysmain and I'll see what effect that has over the next few days.

Thanks too to 'Guru'. I'm a bit reluctant to uninstall Norton at this stage - I'm not sufficiently computer numerate to understand the risk implications of following that suggestion, but I'll bear it in mind if 'TidySean''s solution doesn't have any affect.

- - - Updated - - -

Hello again TidySean! Regrettably your suggested solution hasn't worked - my PC has slowed down again today and is responding at snail's pace as I type this message. Any other thoughts? I'm still reluctant to take up 'Guru''s suggestion of completely removing Norton.

Hugh S said:

Thanks 'TidySean'. I've disabled Sysmain and I'll see what effect that has over the next few days.

Thanks too to 'Guru'. I'm a bit reluctant to uninstall Norton at this stage - I'm not sufficiently computer numerate to understand the risk implications of following that suggestion, but I'll bear it in mind if 'TidySean''s solution doesn't have any affect.

- - - Updated - - -

Hello again TidySean! Regrettably your suggested solution hasn't worked - my PC has slowed down again today and is responding at snail's pace as I type this message. Any other thoughts? I'm still reluctant to take up 'Guru''s suggestion of completely removing Norton.

Hey, maybe sysmain has activated again? Have a look in Task Manager and see if you can see the process that's using the disk.

I found this site where there is quite a large list of things to try. The first I would try is dissabling search.
12 Tips for 100% Disk Usage on Windows 10 Task Manager (2021)

One more thing, it seems you have a HDD in your machine. Upgrade it to a SSD. I find that Win10 works better on SSD.

Have a look at What's my computer doing?



I use it to examine unexplained usage of the hard disk.

Hope this helps...

W10 Tweaker said:

Hi Hugh S

Welcome to Ten Forums.


Most Windows 10 users don't use any third party antivirus apps. Windows Defender is considered more than sufficient protection for the average user unless you spend lots of time surfing & downloading from sketchy type websites.

I use Malwarebytes paid, however; I would never hesitate to uninstall it for testing, if that were indicated. Just stay clear of the nasty sites until you reinstall.

Third party antivirus apps especially Norton & Avast are notorious for causing excessive disk and/or cpu utilization. The direction to uninstall Norton would be normal and considered a standard first step in reducing the variables. You can try other options if you have the time, however; you will most likely be back to this stage again.
@FreeBooter is a very skilled & experienced member & would never provide directions that could risk the security of your PC. You can count on that.


One other possible test to complete before uninstalling Norton would be to boot to Safe Mode. This action will disable all third party apps and should prevent Norton from causing excessive disk activity. I can't say for certain if Norton will be successfully disabled in Safe Mode.

Should booting to Safe Mode solve the problem, boot normally again to confirm excessive disk usage, then perform a Clean Boot to see if disabling ALL non-Microsoft apps besides Norton will also correct excessive disk operation.

If after a Clean Boot & disabling ALL non-Microsoft apps while leaving Norton enabled, you no longer have excessive disk usage, the fault is a product of one of the third party apps that was disabled.

If after a Clean Boot with Norton still enabled, you still have excessive disk usage, follow FreeBooter's recommendation & uninstall Norton.

Norton and Avast had less adverse effect on system performance than Windows Defender in this recent Testing...

Performance Test April 2021 - AV-Comparatives