Windows 10: Why is my PC suddenly at 100% disk usage?

A couple weeks ago I got on my PC and it was ridiculously slow. I tried running a scan with my antivirus and it blue screened. I then turned it on again and checked task manager, where I saw that it was at 100% disk usage. I spent about 5 hours frantically searching on google, trying everything, and nothing worked. For other people it seems that the "system" is causing the high disk usage, but for me it doesn't show that. In the place where it shows you what is causing it, at the top it says 50%, which I'm assuming means it's only showing what is causing half of the usage. I genuinely have no

:)

 

Disk Usage at 100% with nothing running

My PC is running Windows 10 with the latest updates but has suddenly become unusable with disk usage staying at 100% even with nothing running and just the same processes listed in Task Manager as before the problems
started. I've tried a few suggestions found in online forums - disabling Windows Search and Superfetch, adjusting page file size, etc. but nothing has done the trick yet. I don't have any outside anti-virus software installed. I read about the potential MSI
issue but don't have IDE ATA/ATAPI Controllers listed in the Device Manager. Finally, it seems to boot up normally and will have periods where the disk usage drops and it's usable but those moments are brief and it inevitably goes back up to 100% usage.

 

100% disk usage

The most common cause of 100% disk usage appears to be Superfetch and Prefetch, but there are also other causes. You can try disabling both these features and see if it helps.

This article provides steps to disable prefecth and superfetch:

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How to Fix 100% Disk Usage Error in Windows 10

 

100% disk usage and memory usage

Hi,

100% disk usage and memory usage can be caused by a software corruption, running application running on the background and malware or virus infection.

For us to properly isolate the issue and provide an appropriate resolution, kindly answer the questions below:

• Did the issue happen after installing the Fall Creators?
• Did you receive any error messages?
• Can you send us the screenshot of the Task Manager showing the 100% disk usage and memory usage?
• What troubleshooting steps have you done so far?

For isolation purposes, please perform a clean boot to see if the same issue will occur. Refer to this
article for more information on how to perform a clean boot
in Windows.

Looking forward to your response.