I recently bought an Intel 320 SSD (128GB) to place on my laptop (HM55 Chipset). Once the clean copy of Windows 7 was done, I downloaded and installed the Intel SSD Toolbox.
The first time I checked the System Tuner panel, the DIPM setting was disabled which I manually enabled. As a consequence, it's status changed to "Feature is optimized". Note that at this time I was using the Microsoft AHCI default drivers, since the Intel RST drivers were not installed yet.
As soon as I installed the latest Intel RST drivers the DIPM status changed to "Current storage driver does not support DIPM settings. Consider changing to another storage driver compatible with your system".
On the bottom line: Intel RST = DIPM disabled; Microsoft AHCI drivers = DIPM enabled.
Any thoughts? Does anyone else have/had this issue too? I've been googling all day and found nothing. If I can't find an answer here, I doubt I'll get one anywhere else.