I have two IBM M1015 controller cards cross flashed to IT mode with the LSI SAS2 2008 Falcon Storport drivers installed in my WHS 2011 PC and my desktop PC running W7 Pro x64. I added the line HKR, "StorPort", "EnableIdlePowerManagement", 0x00010001, 0x01 to the .inf file for the driver in both cases to enable spindown.
The desktop PC can sleep and resume with no issues, all drives spin up and spin down properly. The WHS 2011 machine, however, cannot properly resume from sleep because afterwards, most of the connected drives have a yellow exclamation point under device manager. I have tried updating the BIOS and all drivers but still cannot get the machine to resume after sleep. It will eventually re-boot itself, but it takes several minutes.
It seems to me that if it is working fine under Windows 7 Pro x64, the identical card/drivers should work under WHS 2011. There is one other difference, however, in that the W7Pro PC is an older Ivy Bridge 3570K and the WHS machine is a new Haswell device (Pentium 3220G). I do have a Haswell certified power supply in the WHS box.
Please let me know if anyone has any suggestions or if you have experienced anything similar.