How best to install Win 7=> 10 in dual boot with XP (seperate HDD)?

I currently have a dual-boot system with Win XP on one hard drive and Win 7 on another hard drive. I am looking into upgrading the Win 7 drive to Win 10 sometime in the next month or two.

(At current, on boot up, it gives me the option of booting into Win or selecting "old versions." This has worked satisfactoraily.)

How best to approach this?

The last thing I want to do is screw the XP drive up; the XP is actually the primary drive (in that all the important stuff is on there); the win 7(10) drive is principally there for new games and as (one of several) data repositories.

I have googled the problem, but not turned up any guides as concrete as the ones in which I referred to to set up my current system.

What I have gathered is that it might be best to disconnect the XP HDD from the system before upgrading 7 to 10, yes?

If your goal is to get the Windows 7 upgraded to Windows 10, just leave everything as it is and run Windows 10 setup.exe from inside Windows 7. If you have room on the Windows XP hard drive, I would make an image of Windows 7 first using Macrium Reflect Free in case something goes wrong.

NavyLCDR said:

If your goal is to get the Windows 7 upgraded to Windows 10, just leave everything as it is and run Windows 10 setup.exe from inside Windows 7.

I had noticed someone had a thread in which they had had problems with this sort of set-up (they had to run some sort of program to allow the OS-boot sequence to run afte installing 10 over 7) which is what prompted this thread - I'd like to try and get it right first time!

NavyLCDR said:

If you have room on the Windows XP hard drive, I would make an image of Windows 7 first using Macrium Reflect Free in case something goes wrong.

My XP drive is pretty much full, I fear. I might have enough space on the external (one of those aforementioned back-ups), but I don't know; I'll have to have a look closer to the actual time.

That said, there's nothing particularly mission-critical on the Win 7 drive aside from save games (which can be backed up to DVD); all the important stuff like documents and whatnot are just back-ups from the XP drive.