Answer

BitLocker and Windows Device Encryption encrypt data before it is written to the SSD and decrypt it when the data is read. These additional processes may increase the workload on the system and storage device.



After encryption is enabled, SSD benchmark scores or file read/write performance may be lower than when encryption is disabled. This could be a normal performance difference caused by disk encryption and does not necessarily indicate a hardware issue with the SSD or laptop.



For more information about BitLocker, Windows Device Encryption, automatic activation conditions, and recovery keys, refer to: [Product Information] Windows Device Encryption and BitLocker



This article applies to all MSI laptops.



Why can BitLocker affect SSD performance?



After BitLocker or Device Encryption is enabled, Windows must perform the following additional operations:




  • Encrypt data before writing it to the drive

  • Decrypt data after reading it from the drive

  • Complete the initial encryption of existing data in the background

  • Manage encryption keys and disk access



When software-based encryption is used, these operations are mainly handled by the system processor. This may increase CPU usage and disk access latency.



When is the performance difference more noticeable?



The performance impact of BitLocker may be more noticeable in the following situations:




  • BitLocker is performing the initial encryption process

  • An SSD benchmark is running random read/write tests

  • Applications or games are being launched

  • A large number of small files are being loaded

  • Large amounts of data are being extracted, copied, or processed

  • The system is already under a high CPU load



Sequential read/write performance may show only a limited difference. However, random read/write performance, latency, and low queue depth benchmark results may be more noticeably affected.



FAQ



Q: How can I check whether BitLocker is currently encrypting the drive?



A: Refer to the following FAQ to check the current device encryption status: [How To] How to Enable or Disable Device Encryption and BitLocker in Windows and Check the Encryption Status



Q: Is it recommended to disable BitLocker to improve SSD performance?



A: It is not recommended to disable BitLocker solely to improve SSD benchmark scores. BitLocker helps prevent unauthorized access to data if the computer is lost or stolen, or if the SSD is removed and connected to another device. Windows Device Encryption may also be enabled automatically after Windows setup is completed using a Microsoft, work, or school account.



To compare performance with and without encryption, back up the BitLocker recovery key and important data first, and then evaluate whether temporarily disabling encryption is appropriate for your usage requirements.