FWIW using driver 188.8.131.525 for trim on the P67, one of the earliest drivers I could find, worked as expected... or should that be unexpected
, IOW trim was successful.
Something to consider though with trim
The SSD may choose to perform the optimization immediately, store the information for later optimization or throw away the hint completely and not use it for optimization since it does not have time to perform this optimization immediately.
In Windows 8, when the Storage Optimizer (the new defrag tool) detects that the volume is mounted on an SSD - it sends a complete set of trim hints for the entire volume again - this is done at idle time and helps to allow for SSDs that were unable to cleanup earlier
Hence the re-trim option in W8 defrag I guess.
I gave SRT a shot on the P67 but no go as is.