I just recently installed Windows 7 Professional 64bit. And i heard that AHCI mode increases hard drive performance. I tried the registry trick, changed the mode from Raid to AHCI and i got a BSOD on startup and changed it back to raid. I'm clueless on what i did wrong is it perhaps a driver issue ?
*In device manager, my storage controller is "Intel(R) ICH8R/ICH9R/ICH10R/DO SATA RAID Controller"
Edit: correct me if i'm wrong in RAID mode doesn't it already enable AHCI by default. and only in IDE mode
AHCI isn't enable. (i'm in RAID mode and only using one harddrive. I installed windows 7 with two harddrives)
Windows 7 should have the SATA driver for your motherboard built in, it is rare to find a motherboard where you have to supply the SATA driver. You could try a repair install but make sure you back up your data first. To be honest you don't notice much difference between IDE and AHCI mode with a hard drive it is only with SSD that it makes a big difference.