Problems with Boot up in AHCI

[dbyun]

hey guys, I did a clean install and followed the DIY step by step on the forum, and I did install the mass storage device matrix or wut not on step 10(followed IBM directions) and installed it before installing a new copy of windows...set the computer in compatibility mode and then I installed like the drivers etc. and then i go back to change it to ACHI and it wont boot windows, get teh blue screen of death

i did a search and found that in compatibility mode it seems alot faster, and indeed that is what i noticed also...but i did not know if it was because the IBM software was now gone

whats the deal? and how do i get back to SATA mode?

thanks