Should I Defrag My HDD Before Converting to SSD?

By Steve Lander

SSDs are fast, light and don't need defragmenting.
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Replacing your primary hard drive with a solid state drive is one of the most significant performance upgrades you can make to your business’ computers. SSDs swap the spinning platters and moving heads of a traditional hard drive for a bank of silent, fast flash memory. They are fast and quiet and aren't prone to the fragmentation problems that plague traditional hard drives.

Defragmenting Your Hard Drive

When you transfer data from your hard drive to your new SSD, the new drive will have to read all of the data that the old drive contains. Defragmenting your hard drive takes all of that data and puts it in a contiguous block. This makes it much faster to read fragmented files, potentially saving time in the transfer process if you are transferring the files that are fragmented and would benefit from defragmenting. Given that an SSD can usually write data faster than your older hard drive can read it, every little bit of performance counts to speed up the initial transfer process.

Transferring to SSD

When you set up your SSD, you effectively have two options. The cleanest choice is to reinstall your operating system and software on your SSD and then copy over any files or settings that you need from the other drive. You can also use the software that many SSDs include in their package to automate the transfer or use of tools built into Windows. If you choose this option, try to clean off your hard drive as much as possible to conserve space on your SSD.

Beyond the Initial Transfer

SSDs don't have to sequentially read data from physical platters like a regular hard drive. Instead, the SSD’s controller can read data from anywhere and everywhere essentially at once. In fact, the controller in your SSD will determine the best place to put data and may even end up fragmenting it intentionally to better balance the use of its memory chips. As such, whether you defragment your hard drive before you transfer its data to the SSD or not won't have any impact on the SSD's performance over time -- it'll just save you a little bit of time in the transfer.

SSD-to-SSD Transfers

If you're already using an SSD as your main hard disk drive and want to upgrade to a newer SSD that is larger, faster or both, it's important that you don't defragment your old SSD before transferring its data to the new drive. First, the old SSD can find data much faster than a traditional hard drive. As such, defragmenting it won’t make any difference in its speed. Also, the large amount of data transfer involved in defragmenting a drive will actually shorten the SSD’s useful life because the memory cells inside of it support a finite number of write and erase cycles. While this won't matter if you plan to throw out the SSD you're replacing, it could matter if you plan to reuse or resell it.