>I have a Samsung disk SSD. https://ssd.userbenchmark.com/SpeedTest/396/SAMSUNG-MZNTD256HAGL-00000
>
>I also have a VHD for my main data on drive d:.
>
>Something appears to make things go slower as months go by. I am still trying to find the reason.

Michel

You should not ever use defrag type tools on a SSD as that will "wear" the SSD quicker than normal. It has something to do with the way they work. In fact, built-in Windows defrag will actually not run when it sees an SSD anyway. You should not full-format an SSD drive for the same reason. Juts use quick format.

Over time of heavy use the SSD will go slower and slower especially as you near capacity.

1) Make sure TRIM is ON in your system: "To confirm that TRIM'S enabled on your WIndows 7 or 8 PC's SSD, open the command prompt and type fsutil behavior query disabledeletenotify (without any end punctuation). If you get 'DisableDeleteNotify = 0' as a response, you're set. If you don't, confirm that your SSD drivers are up-to-date. "

2) You can get Samsung SSD Magician software for free to analyze the drive.

3) See these articles for more:

https://www.howtogeek.com/165542/why-solid-state-drives-slow-down-as-you-fill-them-up/

http://innov8tiv.com/how-to-optimize-and-speed-up-ssd-performance-in-windows-10/

4) Eventually you can "reset" your SSD by doing a secure-erase which marks all its cells as empty and will restore the drive to, essentially, "new" condition. See here:

http://www.ryli.net/ssd-secure-erase-eliminates-the-slowness-of-your-drive/

https://www.pcworld.com/article/2088341/how-to-restore-your-ssd-to-peak-performance.html

https://www.pcworld.com/article/2110095/the-ultimate-guide-to-proper-ssd-management.html

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