AHCI or RAID? Not sure where to post.

Hi. I'm new to the forums.

Is it best to install an OS with AHCI or RAID? I know there are differences, and advantages to each (and to each RAID setup). I plan on doing upgrades soon and want to install a new Vista or Win7 (depending on cost when I look, I may be able to get a cheaper Vista Home Premium).

I learned recently: Some motherboards only allow you to access eSATA external drives with AHCI or RAID setup. Some also allow you to use all internal only if you have AHCI or RAID instead of IDE.

I'v been told to pick which option I want in the bios before installing the OS, and switching them can cause driver conflicts later.

Someone told me Vista does not have AHCI and RAID drivers native to the OS, only win7. But I read contradictory to that. So what is it?

I understand that some motherboards require a person to install AHCI or RAID drivers via Floppy A drive, I'd have to check into a motherboards model obviously. I have heard that a flash card may work, can anyone confirm this?


Thank you.