I am having to replace my motherboard and it will be here Monday (tomorrow) Call this a bad weekend or something for me but for the life me I cannot wrap my brain on which ISO I need. I bought the discounted version for W8 when it was offered by MS. Upgraded to win 8.1 ( clean install) Upgraded to the "preview" release for spring. Anyhow since I am replacing the motherboard, same chipset, mostly, I figured this would be a great time to re-install windows and get a clean install once again. I can't quite figure out if there is already or will be a Win 8.1 update ISO, or if the Win 8.1 ("preview") update is the same that will be release on Tuesday. Any guidance would be helpful. Not sure why I am having a hard time wrapping my brain around which ISO to use this time.