I am on the z87 platform and want to upgrade to z370, possibly that is. Or maybe even rizen actually. Will my OS be saved to my Harddrive or will I have to buy another copy of Windows 10. What are your opinions upgrading from an i7 4790k? Is it worth it.is ddr4 that much better? I think m.2 is cool plus some other stuff . Any great new features I’m missing out on?Any feedback is helpful.