Alexander, Well the origin of my desire to use the Promise raid drivers was the dual boot issue. I have dealt with at least two machines which had been preinstalled with Windows for use as dual boot systems. As far as I know the Promise BIOS level RAID has to be used for Windows to actually do the RAID on such machines. So while on Linux only boxes it won't be a big issue to regress back to the Linux provided software RAID, on dual boot machines this would break the Windows RAID (unless a software RAID for Windows is available). Jack