Currently, I have Windows installed on my C: drive (HDD). If I install it on my D: drive (SSD) aswell, and then format the C drive, will the current C drive (HDD) still be the C drive, or will the D drive (SSD) become the C?
Sorry for poor explaining and confusing question.
PS: I want the HDD as my C: drive
First, when you install Windows to the SSD make sure and have the HDD disconnected. If you don't, your system partition and boot files will stay on your HDD and when you format it, you will erase them and have to fix Windows booting which can get quite involved.
Whatever drive Windows boots from will be C: drive and the other will be D: drive. When Windows boots from the SSD, it will be C: drive.
You can establish somewhat of a permanent file structure by using directory junctions. Google Windows directory junctions and the mklink command.
It is possible to force Windows to install on a different disk or partition whose label is other than C - people have discussed this on earlier editions of Windows. Don't know whether there's a specific issue with Win 10.
However, you want to keep all the partitions associated with your Win 10 installation on the same physical disk (there will be more than one).
But- it's so unusual to attempt this, doing so is bound to cause you problems at some point, and I cannot recommend it.
For interest only (and I'm not going to suggest this is either correct, good practice, the only way, or something to attempt):
here's how you install win7 on a different partition
No problem, boot up into your current OS. When in there, make sure you have formatted the target partition and set it as an Active one.
Insert your Win 7 program disk and navigate to it on your DVD drive using Win Explorer. Click on the setup.exe and the installation will start. Because you are already in C: (and it's therefore locked) the installation will go to the target partition you want, just indicate which partition as you go through the installation process.
I have C: with Vista and G: with Win 7 and every works just fine. New program that you install if you select the WIn 7 option on boot up, will go to G:\Program Files, or whatever drive you have designated.
Adrian
HDD and SSDs do not have a letter hard written in it, it's assigned by OS and it's common that OS assigns BOOT/OS drive /partition letter C:. Other drives are assigned a letter in the order set in BIOS.
One example.
2 HDDs, one with W7 and one with W10. If you boot from drive with W7, that one would be C: and other one D:.
Same computer, BOOT from drive with W10 and it will become C: and drive with W7 drive D:.
If left to default settings, same thing would happen even with one drive divided/partitioned to 2. Other partitions OS may make will be left without any letter and so invisible to Explorer but can be seen in Disk management.
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