Many users report that Windows 11 causes NVMe SSDs to slow down

For example, some NVMe SSDs experience reduced input/output performance per second (IOPS), while others experience reduced read/write speeds. The reduced SSD performance reports are mainly based on comparison with Windows 10.

On the Microsoft forum, user MJ_JasonM said that after upgrading to Windows 11 the random read and write performance of SSDs is reduced by half compared to Windows 10.

In a response to the Reddit forum, a Microsoft employee named Neal Christiansen (reddit account neochristi) seems to confirm that Microsoft is investigating the issue. "Hi, I'm from Microsoft's file system team and I'm investigating this issue," Christiansen wrote.

Windows 11 users also provide SSD performance-related feedback via Microsoft's Feedback Hub. According to a user with the nickname Jeff C, the problem may be related to the driver provided by Microsoft.

"After testing, I found that all NVMe SSDs using Microsoft drivers have problems. However, my Intel 905P SSDs using Intel-supplied drivers are working fine," Jeff C shared.

However, this is still just speculation and the problem may lie in another area.

Neowin's test on a WD SN520 NVMe drive using the CrystalDiskMark tool shows a clear drop in performance. Both read and write performance as well as random writes are greatly reduced.

Let's wait and see how Microsoft responds to this issue.