How can I see if Windows 7 is using TRIM for my SSD drive?

"According to the Crucial User Forums - Is TRIM Running? to test if TRIM is enabled run the following in an administrative command window.

fsutil behavior query disabledeletenotify

If it comes up as 0 then it is enabled.

Have a read of the comments of Support and Q&A for Solid-State Drives and this Intel Community Forum for more info."

"I wrote a command line program to check if TRIM is enabled:
Download & source code

trimcheck
This program provides an easy way to test whether TRIM works on your SSD. It uses a similar method to the one described here, but uses sector calculations to avoid searching the entire drive for the sought pattern. It also pads the sought data with 32MB blocks of dummy data, to give some room to processes which may otherwise overwrite the tested deteled disk area.
The program will set up a test by creating and deleting a file with unique contents, then (on the second run) checks if the data is still accessible at the file's previous location."