Reinstall Windows on a used SSD

[Skinoku]

Hi everyone!
I have an SSD drive used by an old windows installation and i'd like to reuse it.
In the old operating system TRIM wasn't enabled but the drive supports it.
I'd like to know if I simply install Windows 10 Pro on that wiping all partitions and (automatically) enabling TRIM all leftovers left by the old installation will be removed running TRIM command or it will detect and delete only the deleted files (sorr for the word-joke ) AFTER TRIM is enabled and therefore slowing the drive and wearing it out?
I'd just like to know if the TRIM command is retroactive.
Thanks in advance,
cheers!

 

[DracusNarcrym]

Ensure that the partition which contains the previous installation is properly formatted, before you begin the new installation.

As for trimming the drive, Windows should perform that automatically.
If you ever want to do a manual trim of your SSD, you may use the Optimize Drives feature which is built into Windows.

 

[Skinoku]

Ok thank you a lot @DracusNarcrym !
All right with formatting the partition, but I thought that windows had to build up a database of files to delete in order to TRIM work correctly(starting from the first OS boot), so Windows couldn't realize that some full blocks on flash memory used by the old OS aren't still needed and therefore not deleting them throttling the performance during writes...
I hope being wrong (or that there's an easy fix to this)... I now, I'm very paranoic regarding my tech stuff

 

[DracusNarcrym]

Ok thank you a lot @DracusNarcrym !
All right with formatting the partition, but I thought that windows had to build up a database of files to delete in order to TRIM work correctly(starting from the first OS boot), so Windows couldn't realize that some full blocks on flash memory used by the old OS aren't still needed and therefore not deleting them throttling the performance during writes...
I hope being wrong (or that there's an easy fix to this)... I now, I'm very paranoic regarding my tech stuff

The trim command is not governed by Windows, rather by the SSD itself.
Windows can only be programmed to instruct the SSD to execute the trim command, thus internally erasing data which have been marked as not-in-use by the operating system. (this explains why older SSDs couldn't be trimmed, it was not due to any limitations in the operating system, but because of the internal inability of the SSDs themselves)

Do not worry about Windows getting confused over "used" blocks in the SSD flash memory. The data which resides in those blocks is considered as not-in-use by the file system, and Windows will acknowledge that "not-in-use" flag. In other words, any "deleted" data from the previous installation is just sitting there.
It's like having trash everywhere in a room and you just step on them whenever you stand on a specific spot. (really bad example, but you get my point )

So no worries, just run the installation normally and Windows will take care of trimming your SSD when necessary.