Why Windows 11 Mistook My SSD for an HDD and How TRIM Can Save It

Following the latest Windows 11 25H2 update, users of the Surface Pro (Snapdragon X Plus) reported that the system incorrectly recognized the internal SSD as a mechanical HDD. This misidentification leads Windows to apply HDD‑style defragmentation, which is detrimental to SSD health.

SSD vs. HDD Maintenance Strategies

Windows treats HDDs and SSDs differently: for HDDs it runs defragmentation to reorder scattered data blocks, improving read speed. SSDs, however, rely on the TRIM command to mark unused pages, allowing the controller to manage wear and maintain performance.

SSD cells cannot be overwritten directly; they must be erased in blocks (typically 64 pages) before new data can be written. This means the smallest write unit is a page (4 KB–8 KB), while the erase unit is much larger, analogous to erasing an entire sheet of paper to change a single word.

When data is deleted without TRIM, the OS merely removes the file entry, but the SSD controller still sees the old data as valid, causing it to move existing data around during garbage collection. This results in write amplification : writing 1 MB of new data may cause 5 MB or more of actual flash writes, rapidly consuming the SSD’s limited erase cycles.

Impact of Windows Defragmentation on SSDs

By mistakenly applying HDD defragmentation to an SSD, Windows forces the controller to relocate large amounts of data, effectively performing the opposite of what TRIM aims to achieve. Over time, this accelerates wear and reduces the SSD’s lifespan.

The issue appears limited to the Surface Pro 12‑inch Snapdragon X Plus model; other devices are not affected.

Why PowerShell Optimization Fails

Running PowerShell commands such as Optimize-Volume -ReTrim does not resolve the problem because the underlying misidentification persists.

Checking and Enabling TRIM

To verify whether TRIM is enabled, open an elevated command prompt and run: fsutil behavior query DisableDeleteNotify If the command returns 0, TRIM is enabled; a return value of 1 means it is disabled.

To enable TRIM, execute: fsutil behavior set disabledeletenotify 0 Do not disable it (set to 1), as that would worsen SSD wear.

SSD Health Diagnostics

Scanning the SSD (e.g., via built‑in Windows tools) reads each block’s latency; fast responses indicate healthy cells, while consistently slow or failed reads point to bad blocks. This “latency health check” does not affect the drive’s lifespan and can be combined with S.M.A.R.T. data for a comprehensive health assessment.

**Caution:** Avoid using tools that “repair bad sectors” or “clear sectors” on SSDs, as they trigger extensive write/erase cycles similar to the problematic Windows defragmentation.