Many SSD enthusiasts know that the TRIM command cannot be used with files stored on SSDs in RAID volumes. Intel has documented this limitation of IRST for a while now. There are rumors, initially derived from an IRST Readme file, that a future version of IRST would support the TRIM command with SSDs in RAID 0 volumes. Intel has never made an official statement regarding the truth of the situation that I am aware of.
Regardless, ever since the release of IRST 220.127.116.116, the Windows IRST GUI help documentation has contained the following statement:
This feature provides support for all pass-through solid-state drives (SSDs) in your storage system that meets the ATA-8 protocol requirements. Also, support is provided for SSDs that are part of a RAID 0 array. This feature optimizes write operations, helps reduce device wear, and maintains unused storage area on devices as large as possible.
This can be found in the Getting Started section of the IRST Help information, that is displayed when the Help button is clicked in the IRST GUI in Windows. I took that text from the IRST 18.104.22.1687 help information. IRST 22.214.171.1247 was released on 7/24/2012, and IRST 126.96.36.1996 was released about the same time that the 7-series chipsets and Ivy Bridge CPUs were introduced, early in the 2nd quarter of 2012.
There has been no official announcement from Intel about this, and no comments from the PC hardware review web sites. Many SSD users like myself are curious about this, and wish Intel would confirm or deny the truth of the statement included above.
I have my answer, and it is yes, TRIM in RAID 0 works with most 7 series Intel chipsets, with IRST 11.0 and above.
Personally, I want to thank Intel for this. In a sense, we have this now for free, although the development of this was not free for Intel.
At this time, this feature is not available on all Intel PC platforms, which will disappoint some people. Given that this is a new feature, not available on any other platform that I am aware of, IMO we should wait and see if it becomes available on other systems, before we complain about the lack of it.