Windows 11 Pro has an on-by-default setting that could significantly impact your SSD’s performance. The software BitLocker encryption, which is enabled during installation, could slow your system down, potentially robbing as much as 45 percent of the SSD’s speed.

Testing with a Samsung 990 Pro 4TB, the popular tech website Tom’s Hardware found that random writes and reads, which affect overall system performance, suffer the most. While many SSDs come with hardware-based encryption, Windows 11 Pro defaults to software BitLocker, which forces the CPU to handle the encryption and decryption, rather than letting the SSD do it.

Using a Core i9-12900K processor, Tom’s Hardware found that software BitLocker increased latency and decreased transfer rates, while hardware encryption performed similarly to having no encryption at all. In PCMark 10’s storage benchmark, software BitLocker led to a 21 percent drop in performance.

Users can resolve this performance issue by switching to hardware encryption (if available) or disabling BitLocker altogether. For those using Windows 11 Pro, it may be worth checking if software BitLocker is enabled and considering a change.