Hmm, when did this happen? Was it after you shut the machine down (properly), just powered it off without shutting down first or did you lose power?The SSD issues i've seen seem to be related to power cycling machines or losing power, so far..
In order to use trim, you need to use a kernel that is 2.6.33+ and ext4 mounted with the "discard" option. (TRIM won't work unless you have all 3)To overprovision, simply partition the drive using 80% of the unallocated space.
