SSD Slow After Update: Speed Troubleshooting

Quick Answer

An SSD that becomes noticeably slower after a Windows or firmware update is almost always caused by one of three things: a driver rollback, a TRIM scheduling conflict introduced by the update, or a change to power management settings that put the drive into an overly aggressive low-power state. These are fixable without replacing the drive.

Step 1: Check What the Update Actually Changed

Before touching any settings, use CrystalDiskMark to benchmark your SSD immediately after noticing the slowdown. Compare these numbers against the drive's rated sequential read and write speeds. If sequential reads have dropped dramatically (say from 3,500 MB/s to under 1,000 MB/s on an NVMe drive), you are likely dealing with a driver issue or the drive reverting to a slower interface mode. Open Device Manager, navigate to Disk Drives, right-click your SSD, and check the driver version. Windows updates occasionally roll back NVMe drivers to a generic Microsoft inbox driver, which does not support all queue depth and command optimisations that the OEM driver enables. If the driver version changed after the update, reinstall the manufacturer's NVMe driver directly from their website. ## Step 2: Reset Power Management and AHCI/NVMe Settings

Windows updates sometimes reset power plan settings or enable new power saving features that throttle SSD performance. Go to Control Panel, Power Options, and select High Performance or Balanced (not Power Saver). Then open Device Manager, go to your SSD's properties, select the Policies tab, and confirm Write Caching is enabled. For NVMe drives, check that the drive is not forced into a deep low-power state by opening the Windows Registry at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\PCI and looking for your NVMe controller. Some updates enable APST (Autonomous Power State Transition) aggressively, which causes latency spikes that feel like slowdowns during random workloads. Disabling APST through your NVMe driver settings resolves this for many users. ## Step 3: Run TRIM and Check Drive Health

Windows runs Scheduled TRIM automatically, but updates occasionally disable or delay this task. Open an elevated Command Prompt and run: fsutil behavior query DisableDeleteNotify. A result of 0 means TRIM is enabled. A result of 1 means TRIM is disabled. If it is disabled, run: fsutil behavior set DisableDeleteNotify 0 to re-enable it. Then manually trigger TRIM by running Optimize Drives from the Start menu and clicking Optimize on your SSD. Also run SMART diagnostics using CrystalDiskInfo or your SSD manufacturer's tool to confirm no underlying health issues exist. If reallocated sector counts are rising or the drive reports unusual temperatures, a hardware problem is the culprit rather than the update itself. ## Frequently Asked Questions

Will reinstalling Windows fix SSD slowdowns caused by updates? A clean Windows install does resolve driver conflicts and reset power settings, but it is a heavy-handed approach. Try driver reinstallation, power plan reset, and TRIM optimisation first. Reserve the Windows reinstall for cases where the drive passes SMART diagnostics but performance remains degraded after all software fixes. Can a Windows update corrupt an SSD? Direct corruption from an update is rare but not impossible. More commonly, updates interact badly with existing firmware, which is why keeping your SSD firmware updated before major Windows updates reduces compatibility issues. Check your SSD manufacturer's website for the latest firmware version. My SSD shows full health in diagnostics but still feels slow. What else should I check? Check your SATA or M.2 slot. Some motherboard BIOS updates change PCIe lane allocation, potentially dropping an M.2 slot from PCIe Gen 4 to Gen 3 or lower. Verify the interface speed in your BIOS settings and in CrystalDiskInfo under the Transfer Mode field.