Counterintuitively, a person should NOT turn off auto defrag when they install an ssd. (this advice applies to windows ten ONLY) However Windows 10, (scott says 7 and 8 also received a defrag update), not only recognizing you have ssd, but also using a different, less invasive method for defragging your ssd, this defrag is set ON if you have system restore enabled, I recommend TURNING IT ON even if you do not use system restore. This new type of deffrag does indeed increase performance, and does indeed increase the life of your ssd. Scott Hanselman for Microsoft, blog post, http://www.hanselman.com/blog/TheRealAndCompleteStoryDoesWindowsDefragmentYourSSD.aspx ...It’s also somewhat of a misconception that fragmentation is not a problem on SSDs. If an SSD gets too fragmented you can hit maximum file fragmentation (when the metadata can’t represent any more file fragments) which will result in errors when you try to write/extend a file. Furthermore, more file fragments means more metadata to process while reading/writing a file, which can lead to slower performance.” Windows is not foolishly or blindly running a defrag on your SSD every night, and no, Windows defrag isn’t shortening the life of your SSD unnecessarily. Modern SSDs don’t work the same way that we are used to with traditional hard drives. Your SSD’s file system sometimes needs a kind of defragmentation and that’s handled by Windows, monthly by default, when appropriate. The intent is to maximize performance and a long life. If you disable defragmentation completely, you are taking a risk that your filesystem metadata could reach maximum fragmentation and get you potentially in trouble. IN ADDITION, this new type of defrag actually INCREASES ssd life; the newer defrag addresses "trim" TRIM lets the operating system notify the SSD that a page is no longer in use and this hint gives the SSD more information which results in fewer writes, and theoretically longer operating life.