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Does my NVMe SSD support hardware-accelerated BitLocker for better speed?
Microsoft recently confirmed that enabling BitLocker on modern PCs equipped with NVMe SSDs impacts system performance. While historically, the encryption overhead was negligible—often in the single digits—the landscape has changed with Windows 11 version 24H2. This update makes BitLocker a default feature for new installations and modern devices.
The core issue lies in the capabilities of modern hardware. NVMe drives have become exceptionally fast, capable of massive Input/Output (I/O) operations per second. When BitLocker runs in software mode, your CPU must encrypt and decrypt this flood of data in real-time.
Consequently, your CPU faces a bottleneck. It cannot process the Advanced Encryption Standard (AES) calculations fast enough to keep pace with the drive’s speed. This results in high CPU utilization, which directly degrades performance in resource-heavy tasks.
Real-World Impact on Your Workflow
You will likely notice this performance penalty during activities that demand high drive throughput and simultaneous processing. The bottleneck manifests as stuttering or extended load times in:
- Gaming: Loading assets and textures rapidly.
- Video Editing: Scrubbing through high-resolution timelines or rendering.
- Development: Compiling massive codebases.
Microsoft notes that while data protection is valuable, this software-based decryption steals critical CPU cycles needed for your applications.
The Solution: Hardware-Accelerated BitLocker
To resolve this bottleneck, Microsoft introduced support for “hardware-accelerated BitLocker” in updates following September 2025 (KB5065426). This feature fundamentally changes how encryption is handled.
Instead of forcing your main CPU cores to handle the heavy lifting, this feature offloads the cryptographic work to a dedicated engine within the System on Chip (SoC). This shift allows your main CPU to focus on running applications, drastically reducing overhead. Early testing indicates a reduction in CPU cycles by over 70%, which also extends battery life on laptops.
Benchmark Analysis: Random I/O is Critical
Microsoft released benchmark data comparing Device A (Software BitLocker) against Device B (Hardware-Accelerated BitLocker) using the CrystalDiskMark tool.
The results highlight a crucial distinction: sequential speeds (large file transfers) remain mostly unaffected. However, random I/O operations—which mimic how operating systems and apps actually work—show massive gains with hardware acceleration.
- Sequential Read/Write: Negligible difference (+0.6%).
- Random 4K Read (Q32T1): Hardware acceleration is 2.3x faster.
- Random 4K Write (Q32T1): Hardware acceleration is 2.3x faster.
- Random 4K Read (Q1T1): Hardware acceleration is 40% faster.
This data proves that hardware acceleration removes the latency in small, frequent file operations, making the system feel significantly snappier.
Hardware Requirements and Verification
This performance fix is not universal. It requires specific hardware capabilities. Currently, Intel Core Ultra Series 3 (“Panther Lake”) processors are the first to support this offloading feature natively, with other vendors expected to follow.
To verify if your system is currently utilizing this feature, you must use the Command Prompt.
- Open Command Prompt as an Administrator.
- Type manage-bde -status and press Enter.
- Look for the Encryption Method field.
Interpreting the Results:
- If you see “XTS-AES 256”, you are using software-based encryption (Potential bottleneck).
- If you see “XTS-AES 256 (Hardware accelerated)”, your system is optimized.
Windows 11 automatically enables this feature if your hardware supports it and you have installed the necessary updates. There is no manual toggle to force this transition on unsupported hardware.