Can I use DiskPart to split my C drive into two?

Potato12

Just got a pre-built gaming PC and the manufacturer put everything onto a single 1TB C drive. I really want to separate my Windows OS from my games (create a D drive for Steam, etc.).

A Google search led me to DiskPart. I think the command is shrink? But I have no idea how it works. Do I just type shrink and magical things happen, or do I need to specify numbers? How do I tell it to cut exactly 500GB?

Any advice for a tech dummy would be greatly appreciated. I don't want to break my brand new PC!

Kiki

Potato12

Hey mate, good question!
Yes, DiskPart can do it. But you need to be careful. If you type the wrong thing, no second chances. Here's the DiskPart way for cutting exactly 500GB off a 1TB drive:
Open Command Prompt as admin → type diskpart
list volume (find your C: drive, probably Volume 0 or 1)
select volume X (replace X with your C: number)
shrink desired=512000 (that’s 500GB in MB)
No shrink alone won’t do magic. You need the desired= part unless you want the default (usually tiny).
It’ll say “shrunk successfully” – then type create partition primary
format quick fs=ntfs label="D Drive"
assign letter=D
But here’s the catch:
You can’t shrink past where unmovable system files sit. So even if you ask for 500GB, Windows might only let you shrink by, say, 300GB. That’s normal.