The problem isn’t new, reports of this issue go back several months, even while the OS was still in preview, but nothing seems to have changed after Microsoft decided to launch Windows 11 on October 5, 2021. In the Microsoft forums, user “MJ_JasonM” explains his experience and share a screenshot of the drive performance on Windows 10 and then after upgrading to Windows 11. On Reddit, a Microsoft employee has acknowledged the company investigating the issue, but this happened several months without an official follow-up. In another thread, user MahtiDruidi on Reddit shared another screenshot showing noticeable slower write speeds on NVMe drives. The root of the cause is still unknown since the software giant hasn’t acknowledged this as a problem. However, some users have mentioned that the performance issue could lie in the virtualization-based security (VBS). Others have discovered that the issue only happens on the drive that contains the Windows 11 installation. For instance, if you run a benchmark on a secondary drive, the reads and writes speeds do not change significantly compared to Windows 10. For example, a screenshot was posted in the Microsoft forums showing a significant difference in speeds on two top-of-the-line Samsung 980 Pro NVMe SSDs on the same machine. You can also find similar complaints in the official Feedback Hub. One user confirmed its 1TB Samsung 970 EVO Plus NVMe drive running Windows 10, the popular CrystalDiskMark benchmark tool, reports random write speeds around 750-850MB/s. However, on Windows 11, the random write speeds are only around 200MB/s on the 970 EVO Plus and 980 PRO. In response to this post, other users reported similar findings when running benchmarks on their devices using NVMe drives. Microsoft has recently released the update KB5007262 as a preview for Windows 11 that bumps the version number to build 22000.348, which some user reports have shown signs of speed improvements, but it doesn’t fix the problem. All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.