Originally Posted by kgtuning
Can I install Windows 10 on a drive and install a flavor of Linux on another then unplug the drive I'm not using and plug in the drive I want to use
Well, yes and no.
If you stop and think about it, when you install any OS there has to be a way for the computer to find the files it needs for booting and running that OS.
Back in the days when computers were being invented it was decided that all computers
load a tiny snipit of code from the first sector of the first drive (drive 0, also called the Boot Drive) into their memory and then execute that code right after post (Power On Self Test - a hardware check). That code tells the computer where the boot loader is located and then the computer loads and runs the boot loader. The boot loader tells the computer where the files are that it needs for starting the OS. The OS files can be on any drive, any partition - just so long as the boot loader points to them.
So, when you say "install Windows 10 on a drive" what you are doing is putting the Windows 10 windows folder (and associated folders like Documents And Settings, Program Files, etc), on that drive, be it Drive 0, Drive 1, Drive 10, whatever. Drive 0 still gets the code that tells the computer where you decided to put those folders when you ran the Windows Install program.
Now back to your original question:
If you remove Drive 0 from the computer it will not boot - because it won't be able to find the boot loader. You get the "OS Not Found" error.
When you set up multi-booting the boot loader has to be modified to point to all of the folders
that contain OS files and to pop up a screen that lets you choose which OS folder to use (ie, which OS you want to run). So, in the scenario you propose if the Windows folder is on Drive 0 and the Linux folder is on Drive 1 and you remove Drive 0 - No boot. If you remove Drive 1 (the"Linux drive") and choose Windows from the boot loader screen Windows will still boot, but you'll get the "OS not Found: error if you choose Linux from the boot loader choice screen.
I know what you're thinking now!
If I install Windows to Drive 0 and then remove that drive and then install Linux to another drive (that would now be the new Drive 0) I can boot either OS by just removing the drive with the OS I don't want to run.. That's true, but you'd have to be plugging and unplugging drives to make it work. You could just change the boot order in the BIOS in order to switch which OS you want to run (the boot loaders on the two Drive 0s would be different). There are a lot of other messy issues with doing it those ways that in my opinion make it not worthwhile to do, but it can be done. There's just no reason to do it.. Having a Drive 0 with a proper boot loader is the right way to multi-boot.
Keep in mind that the Windows boot loader can not load Linux . You need a third party boot loader to run them both.
Edited by billbartuska - 7/18/16 at 1:31am