By Michael / Last Updated May 12, 2023

Before using Partition Assistant we highly recommend you do a complete defragment on the partition which you want to resize. The built-in defragment tool could assist you achieve this goal. Here are two methods of "How to defragment partition in Windows OS".

What is defragmentation? And why defragment partitions?

Defragmentation is a process of reducing the fragmentation on your partition or a disk and organizing the data on it to improve the performance of your computer. It is usually performed when you need to optimize an SSD or HDD.

When you operate your computer, the operating system will store some file that is not invisible to you in clusters of partitions. and those files will slow down your PC's running speed. Thus, it is necessary to defragment partition or hard drive at regular intervals.

Next, we will show you how to defragment your partition with 2 methods.

✍Attention: You should not defragment a solid state drive because it will reduce its life span. And a SSD can efficiently read data in cluster, so it is actually unnecessary for it.

How to defragement partition and hard drive?

You can follow the steps to run the Windows built-in disk defragment tool.

Step 1. on the Desktop, click "Start" button, and open "Control Panel"

Step 2. In the Control Panel, navigate to "System and Security" > "Defragment hard drive"

Step 3. And the Disk Defragmenter will be open, and choose the partition and disk you want to defragment, and choose "Defragment disk".


Note: To launch the Defragment tool, you can also go "Computer Management MMC", and open "Disk Defragmenter".

Other tips to optimize the performance of your hard drive

Besides defragging, there are some other ways to optimize the performance of your hard drive: 

1. Ensure System is Running in AHCI Mode

If your system disk an SSD, you can check if the system is running in AHCI mode. Just tap the BIOS key to BIOS setup during the booting process. And you can change the SATA controller mode to AHCI mode.

2. Extend the C partition

Generally, the C partition is where your system stored. It needs enough free space to guarantee a smooth running speed. And you can extend the C partition with the powerful partition manager, AOMEI Partition Assistant Professional