Expanding a partition to another drive

I don't know how to extend C Drive (in my SSD: 256GB) to my HDD (1TB), Is there a good way? I know in some IOs it will make my speed equal to HDD (in those which gonna be written on HDD obviously but, if it decreases all IO speed to HDD tell it to me) I attempt to search for "making a partition in another drive and append it" but I got no good results on the internet over how to do it, also I don't know much about RAIDs I feel maybe they have a solution for me but they are "wipe them all first" actions and that makes me worried to take any action, also I do not have a backup or storage to back up into. so don't tell me to back up and do action x also I'm a noob in StackExchange if I'm in a wrong place, please tell me

OS: windows

The only way you can accomplish this if both drives are in a RAID type of configuration. This can be achieved using a hardware RAID and software RAID. If you use a hardware RAID, you will have to format all drives that you want to use before you can setup a striped RAID. Software Raid can be converted into a dynamic disk without format though.

For Software you only have to make sure you have enough room on one of the drives so you can expand the other partition into that drive.

If you are on Windows, you can open Disk Management, convert your drives to a dynamic disk and then expand a partition to another drive.

There is a caveat, once your disk has been converted to a dynamic disk, it is windows only. You cannot dualboot another non-windows OS. Also, converting back to a non-dynamic disk can only be done by completely erasing the disk.

I cannot tell you how much it will affect speed, but chances are big that the speed will be greatly reduced for every file as a striped volume will write data to both drives for every file to spread the load.

Now... that said, there are other tricks you can do that somewhat do what you want.

Instead of expanding one partition into another drive, you can create mount points on one drive that redirect to another partition.

This essentially means that you could have your entire steam library on your C drive, move that to the D drive, then create a mount point on the C drive and everything works again without having to reinstall any game.

There are multiple ways to do this. From disk management, you can add a drive letter to any drive, but also a folder path. That folder cannot exist yet, but you can first rename the old folder to something else, create that mount point, then move all data from the old folder to the new folder.

Another way is by using mklink from a command prompt run as administrator. This allows you to create a junction between two places somewhere on your drives.

You could make C:\MyGames be a junction that points to D:\Games\Relocated

From that point you can find your games both at C:\MyGames and D:\Games\Relocated.

In all cases, even though you have a folder on C:... it is replaced with a mount point, so the actual data is not on C and thus not taking up space.