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Slow Performance on an SSD: 6 Common Causes

October 6, 2023

Solid-state drives (SSD) generally read and write data much faster than conventional hard disk drives (HDDs). After all, that’s one of the major advantages of the technology. 

Hard drives must move their read/write heads to different portions of the platters (magnetic discs that store the user’s data). SSD drives store data electronically, so there are no moving parts — and virtually no lag when the user accesses a file.

But certain issues can cause SSD performance to suffer. If your computer boots slowly or if you notice a considerable drop in your drive’s performance, that’s a serious symptom; in many cases, slow performance indicates an impending SSD failure.

Below, we’ll discuss several common issues that can impact SSD performance. First, a quick warning: If your SSD runs slow, back up important data immediately. If your drive fails without a backup, data recovery may be possible — but a good backup will save you quite a bit of time and money. provides comprehensive services for SSDs, and we support our services with a no data, no charge guarantee: If your data isn’t recoverable, you don’t pay for the attempt. Call 1-800-237-4200 to get started.

Why an SSD Runs Slow: 6 Common Reasons

1. Outdated or Corrupt Firmware

Firmware refers to the operating instructions that your SSD uses to store data and interface with your computer. Generally, an SSD should work straight out of the box — but some firmware updates are crucial, as they can impact TRIM operation (discussed below) and other operations that impact performance.

Check with your SSD’s manufacturer for instructions on updating the firmware. Remember, firmware updates are an intensive operation, so back up all important data before attempting an update.

2. Disabled TRIM Command

The TRIM command is essential for SSD operation. It allows the operating system to tell the SSD which blocks of data aren’t in use — the SSD can then wipe out those blocks and write data efficiently. 

For a detailed explanation of the command, read: What is the TRIM Command on Solid State Drives? 

However, if you’re not interested in the specifics, you simply need to know that TRIM should be enabled (unless you’ve got a very, very good reason to disable the setting). 

Windows Central provides a guide for checking whether TRIM is enabled — but TRIM is automatically enabled in Windows 10 when the system detects an SSD.  Unless you’ve changed something intentionally, you can move on to the next potential cause.

3. AHCI is Disabled

Advanced Host Controller Interface (AHCI) is a programming standard for SATA devices that enables native command queuing and hot-plugging. Those features aren’t essential for SSDs (and we’ll refrain from going into much detail about how they work, at least in this article). 

But while AHCI is arguably optional for SSDs, most drive manufacturers recommend enabling AHCI. The reason: Operating systems expect AHCI, and enabling AHCI may allow an SSD to “play nice” with other storage devices (such as hard drives). 

If your SSD was operating smoothly, then suddenly lost speed, AHCI is probably not the culprit — but if you’re installing a new drive and you’ve changed your AHCI/IDE setting (AHCI is almost always enabled by default), you may need to change it back.

4. Virus/Malware Damage

Malware can interfere with computer operation, slowing down read/write processes significantly. 

Make sure you have an up-to-date antivirus solution — and if you notice signs of ransomware or malware infection, we strongly recommend that you contact a professional data recovery laboratory before taking additional steps. 

5. The SSD Is Filled Near Its Capacity

SSDs need empty space to operate predictably. That’s due to the intricacies of solid-state storage: NAND devices can only write to an empty page, which is why advanced garbage collection algorithms are so important. 

The rule of thumb is to leave at least 20% of your SSD’s total capacity empty. You can occasionally cross that threshold — it’s a rule of thumb, after all — but you’ll need to provide enough space for cache operations.

This also applies to hard drives, by the way: Hard drives should not be filled to capacity, since the device needs to accommodate the inevitable bad sectors that occur through normal operation.

6. Failing NAND Memory and Other Issues

If an SSD gradually slows down, it’s possible that it’s simply coming to the end of its natural lifespan. No storage device lasts forever, and while SSDs generally last for 5-10 years, some may fail earlier due to operating conditions, user storage habits, and for various other reasons. 

It’s also important to remember that other issues can cause computer slowdown — the performance problems may be related to software, not hardware. 

But ultimately, it’s wise to treat a slow SSD as a serious issue. Back up your data to a separate device and consider replacing the drive before it fails — particularly if it’s your primary storage device.

SSD Data Recovery Services from

If you lose data due to an SSD failure, a hard drive failure, or for any other reason, we’re here to help. provides risk-free evaluations and a no data, no charge guarantee, and through years of research and development, we’ve maintained the industry’s highest success rates for SSDs and other storage technologies.

To get started, call 1-800-237-4200 or schedule an evaluation online.