Recently my computer started not working as fast as it used to. Applications were slow to launch and file operations were delayed. I started digging with regular tools that I trust, e.g. Task Manager, Resource Monitorand CrystalDiskInfo, and everything continued to point to storage. At first my assumption was obvious. I understand SSD may be worn out or starts to malfunction, which is what most people think about when the system suddenly starts to feel sluggish.
What surprised me was how wrong this assumption turned out to be. After going through a quick checklist and fixing a few Windows-level issues, my system was noticeably faster again. No new equipment, no reinstallation, no radical measures. Just a few quick checks that most people don't even think about. If your computer is running slower than it should and you're concerned that your SSD is on its last legs, this is the same checklist I use before blaming the drive itself.
What TRIM does and why it matters for SSD performance
TRIM is one of those SSD features that does most of the heavy lifting in the background. When you delete files on an SSD, the data isn't actually erased right away. Without TRIM, the drive doesn't know which blocks are actually free, so it has to do extra cleanup work before it can write new data. Over time, this additional overhead accumulates and performance slowly degrades, especially with large numbers of small writes. TRIM fixes this by allowing Windows to tell the SSD which blocks are no longer in use so the drive can clean them up early and stay fast rather than constantly playing catch-up.
On most Windows systems, TRIM is turned on automatically, so turning it off can be surprising. This can happen after cloning a disk, restoring from an older system image, switching storage controllers, or upgrading a much older Windows installation. In other words, it doesn't mean your SSD is faulty. This simply means that Windows at some point stopped sending TRIM commands, often without making it obvious.
It only takes a minute to verify that TRIM is enabled. Open the Start menu, type Command Prompt, right-click it and select Run as administrator.
In the command window, type the following command and press Enter.
fsutil behavior query DisableDeleteNotify
If you see a value of 0, TRIM is enabled and working as expected. If it returns 1, TRIM is disabled. On my system, TRIM returned a value of 1, which meant it was disabled for some reason. If you find this, enable it by running this command and pressing Enter and you're done.
fsutil behavior set DisableDeleteNotify 0
No reboot is required and there is no downside to enabling it on an SSD. This is one of the fastest checks you can perform, and it addresses a surprisingly common cause of slowdowns before they develop into more serious performance problems.
How firmware affects SSD performance and stability
SSD firmware is another thing that's easy to overlook, mainly because Windows never displays it in any meaningful way. However, firmware controls how the drive handles caching, garbage collection, wear leveling, and even how it responds to certain workloads. When it is out of date, performance may suffer slightly, especially after OS updates or prolonged heavy use. In some cases, vendors also fix obvious performance bugs or compatibility issues with firmware updates, but if you never look, you'll never know those fixes exist.
Checking your SSD's firmware usually means contacting the manufacturer directly. Tools like CrystalDiskInfo will show you the current firmware version, which you can then compare with the version listed on the manufacturer's support site or in its official utility. Most major SSD manufacturers provide a simple update tool that will handle this process for you, but you should always make a full backup first before touching the firmware.
In my case, my SSD's firmware was not updated, and updating it revealed another potential reason for the slowdown. Nothing needed replacing, but it was an important step before blaming the drive itself.
How lack of free space affects SSD write performance
On an SSD, the available space directly affects how efficiently the controller can do its job. Without enough space to work with, performance, especially write performance, drops much faster than most people expect. When a drive gets full, it loses room to breathe and performance, especially write performance, can suffer. This is why an SSD that tests well when it's new can start to feel sluggish once it's full, even if the drive itself is still perfectly fine.
The simplest solution is also the most boring: make room and leave it free. As a general rule, I try to leave at least 15 to 20 percent of my SSD empty to give the controller room to work. This means deleting software I no longer use, clearing out large downloads, and moving media or archives off my drive if necessary. Luckily, I had enough space on my SSD so I was able to rule out this issue.
If you want to go even further, some SSD tools allow you to explicitly reserve excess space, but even without that, leaving enough free space achieves the same goal.
What does write caching do and why is it important?
Write caching is one of those Windows settings that most people never touch, but it can have a real impact on day-to-day work. SSD performance. When this feature is enabled, Windows can group and reorder writes so that the drive doesn't stop and start constantly. If it's disabled, every small write must be done immediately, which can noticeably slow down file copying, installation, and overall system activity. Windows sometimes disables write caching after certain errors, driver changes, or power events, and this is not always obvious.
It's easy to check. Open Device Manager, expand Disk Drives, right-click the SSD and select Properties.
On the Policies tab, make sure the Enable device write caching checkbox is selected. For most desktop and laptop systems, it is safe and recommended to leave this option enabled, especially if you are using a system with a battery or reliable power source.
After making sure this feature was enabled, I was able to rule it out as another potential cause of slowdown and continue with the checklist.
How to detect background disk activity in Windows
Before you assume that the problem is with your SSD, it's worth checking to see if it's busy. A healthy SSD can be slow if something in the background is constantly reading or writing data to it. Cloud sync tools, virus scanning, search indexing, backups, and Windows updates can all keep disk activity high for long periods of time without explaining why. In my case I use Sync to sync folders on multiple systems, and I initially suspected that this might be contributing to the slowdown.
A quick look in Windows cleared things up. In Task Manager, I watched the Disk column and could see when usage remained consistently high rather than briefly spiking. Resource Monitor makes it even easier to determine what's going on by showing exactly which processes are accessing the disk in real time.
In particular, Syncthing performs a lot of small file operations when it scans or syncs, which can cause the SSD drive to run slower while running, even if the drive itself is fine. Once I took this background activity into account, it became much easier to distinguish between a truly slow SSD and an SSD that was simply busy doing its job.
By the time I worked through this checklist, it became clear that my SSD was not failing at all. It was a mixture of small Windows issues, background activity, and a few easy-to-miss settings that gradually degraded performance over time. Once these issues were resolved, my system became noticeably faster again without replacing hardware or reinstalling Windows.
- Storage capacity
-
2 TB
- Hardware interface
-
PCIE x 4
If your computer is running slower than it should and you're concerned that your SSD is on its last legs, I'd do the same checks first. Sometimes the fix is a few minutes of cleaning and testing rather than a new drive.
