It's been a while since I've looked at trim but some good news, RAID0 trim seems possible with pre-7 series chipsets.
Tested on ASUS P67 EVO
Running 11.6 OROM and 11.2 driver with no modification on W7SP1x64 with 2x V4 in RAID0, sectors 16 thru 31 were filled with 8KiB of test data and some crude software written to send a trim command to unmap them. The command was rejected by the driver, no trim performed.
After some rough modification (needs sorting out when I have the time) for personal educational purposes
, using the same V4 setup the LBA's of a picture file was recorded using Winhex then the file deleted.
Success, the file was trimmed as seen by all ones being returned for the trimmed LBA's. Note that returning all ones is specific to V4 SSD firmware, other SSD's may return all zero's instead.
Same setup with 2x 60GB Agility 3 in RAID0 and writing 8x 1GiB files of incompressible data.
And after deletion.
If trim were not working we would still see the big dip in read performance.
Switching to W8DPx64 and 11.5 drivers using the 8KiB of test data written to sectors 16 thru 31.
Vertex4 RAID0 before
Vertex4 RAID0 after
Agility3 RAID0 before
Agility3 RAID0 after
Note that Agility3 SSD firmware returns zero's for unmapped LBA's.
There does seem to be a little bugginess with the trim, even with Z77, so maybe Intel are working on that before making RAID0 trim more widely available, I hope so.
It would have been interesting to have looked at trying SRT on P67 and 5 series RAID0 trim but unfortunately I have little to no time for this for now.