To check trim open an elevated command prompt and thter this command fsutil behavior query disabledeletenotify
It will return - DisableDeleteNotify = 1 (Windows TRIM commands are disabled) or
DisableDeleteNotify = 0 (Windows TRIM commands are enabled)
The only issue is that will tell you if the Operating system is sending trim commands to the sata controller, it won't tell you if the controller is using those commands. We know the Intel controllers do, but there is a lot of speculation of whether the Marvel controllers do. I guess, time will tell.