I installed a new version of windows XP on a 120 gb SSD in a dell 1520 laptop. I was attempting to optimize the new SSD from an SSD optimization guide. I have accomplished all except enabaling AHCI. I have already installed the OS and now do not know how to get it to go into AHCI. I went to the dell website and attempted to download the appropriate drivers for the matrix storage manager version 7.0.0.1020, A02. It downloaded okay, but when I attempt to switch to AHCI in the BIOS and restart I get the blue screen of death. Please help me to get this system into AHCI preferably without reinstalling the OS again. If it comes to reinstalling how do I get XP to install in AHCI mode?