Solid-state drives have supported TRIM for years in order to maintain performance over time. But the command has never worked on SSDs configured in RAID arrays – until now, that is. Intel has released a new Rapid Storage Technology (RST) driver that enables TRIM for those using Intel drives with a RAID-0 array, although for now it's limited to Windows 7 systems with Intel 7 series chipsets.

TRIM allows an operating system to inform the SSD which blocks of data are no longer considered in use and can be wiped internally – without it they would be marked as available but remain occupied with old data. There's an additional overhead after a delete but as a result  performance is improved dramatically since you don't have to deal with that while writing new data, when you're more likely to notice it. This is especially important as the drive fills out since performance will degrade without proper garbage collection.

Last year users were led to believe that RST 9.6 drivers would add TRIM support in RAID volumes, but Intel later clarified that it was only for SSDs acting as single drives in AHCI mode alongside a separate array attached to the same Intel storage controller. An example of this would be users that want an SSD as a boot drive for increased performance but still be able to RAID multiple HDDs together for storage.

Now, it's possible to configure SSDs in high-performance RAID-0 arrays to achieve even faster speeds. AnandTech has put the new drivers to the test and confirmed that TRIM is indeed functioning as expected, achieving over 1GB/s of sequential read performance and over 300MB/s in sequential writes with a couple of 64GB Samsung SSD 830 – individually they're rated for 500MB/s reads and 160MB/s writes.

For those keeping scores that's 128GB of SSD storage capable of gigabyte read speeds for around $150.

Intel is working on Windows 8 compatibility but apparently last-generation 6-series motherboards are out of the picture, despite the fact that they share the same storage controller logic as the 7-series.

Download: Intel Rapid Storage Technology RST Driver for Windows 7 32-bit | 64-bit