The SSD will have the operating system and applications.
The 1TB drive is for storage of all my media files.
The 2TB I want it to have a copy of all my files from SSD and 1TB, and then I'll have 2000gb - (1000gb + 128gb) = 872gb left over. I want to use this 872gb for extra storage.
Is this possible? Is this the right idea? First time here thanks all
Yes; it's possible. If you're going to use the 2TB for backups, keep it for backups. Though, it's a bit of a pain and not as efficient. RAID + backup scripts is another choice for media files. Backing up the boot drive is tough to roll back out. That gets tricky, especially with Windows's (I'm assuming you use Windows) registry system.
You don't need to create a RAID array. Just use them separately as drives C:, D:, and E:.
Install your Operating System with just your SSD connected and that will be your C: drive.
When that is done shut down and connect your other 2 drives. Windows should recognize the drives and automatically ssign them drive letters; if not then go into Windows Disk Management and manually assign them drive letters.
RAID is not backup. RAID is redundancy/uptime. RAID allows you to keep using your computer if a drive dies. Sort of like cars that have run-flat tires. If you get a flat you can keep driving until you reach a service station or home.
Thanks dereck! I'll look into software.
I don't understand what you mean by Raid though. Can you please explain it a bit more, I looked it up on wiki and it seems it synchronizes two hard drives? So is there no real advantage to it for a casual user? I'm worried about loosing family photos.
No; that's not true. The point of RAID is for redundancy. Let's say you have a 5x 3TB HDD. So that's a total of 15TB of space, or so they're advertised. But let's just say that it's 15TB. Now, if any of the drives dies, you lose any data that you stored in them.
RAID carries a redundancy block across all drives. RAID will take up a full drive, so instead of having 15TB of usable space, you have 12TB. That's not to say that RAID lives inside one single drive. RAID will have redundant blocks across all drives. And data is also not stored into any single drive, but rather compartmentalized into all drives. With the RAID algorithm, if any drives dies, you will still have access to your data. If you replace the dead drive, RAID will recalculate and re-sync the new drive.
But please don't assume that based on what I said, RAID = backup. RAID is not backup. Even with RAID setup, it cannot replace backups.