A first for me... In a test laptop (an older but solid DELL E6500 Core2Duo at 2.9ghz) containing an older (but no too old) OCZ Agility 3 series SSD, I do tons of OS, application, HDD/SSD and image restoration testing. It serves me well. Since a lot of my testing includes CLEAN INSTALLs of various Windows versions as well as image restorations done by apps which do not TRIM the SSD upon restore (Macrium REFLECT is the only one I know that can do that), the SSD's Garbage Collection would be the only real source of proper TRIMming/CleanUp within the SSD... I typically do not use OPTIMIZE in the OSes I test with during the testing phase. While tracking down a Windows 10 update failure issue due to lack of something that should have been on the System during the update, the tracking process threw out a DISK FULL message during the process even though Windows and its Disk Mgmt stated there was about 70gB free space on the 120gB SSD (no, I DO NOT USE Rollback RX which has a similar problem). This was strange so I ran the tracking procedure once again and received the same hard DISK FULL message from the OS... this happened over and over again Thinking about the situation a bit as to how this System has been used mostly, I wondered if the SSD, internally, was carrying around tons of DATA from previous work that had never been TRIMmed properly by the OS or by the internal Garbage Collection process. Since I was running under Windows 10 at the time, I decided to run a manual OPTIMIZE process on the SSD's only partition which ran to completion successfully. Following that I re-ran the problem tracking process (the one with the hard failure) and it now ran to completion without issue. Apparently the SSD had been carrying around appx. 70gB of old DATA and that the internal read/modify/write process (used to make storage available when all their CELLs have bee used) had all but exhausted available space. The whole thing was an interesting observation in what can happen to an SSD over time when not TRIMmed properly, or whose Garbage Collection may not be as sophisticated as the newer SSDs may have. Has anything like this happened to any of our Forum users that currently use SSDs (most by now I would assume)?