That will only work for the molex connectors. For the 4 pin CPU connector and the 24 pin motherboard connector (As well as any PCI-e connector) you'll need a different tool.
Mind that each cable has specific wire placings. The 4 pin molexes are easy, because you just need to remember which side the red or yellow is on. I would recommend with just starting on the 4 pin Molexes. That's what I did, and it worked nicely. Doing the rest of the cables would be quite a chore. Just think about the pain of remembering where all 24 cables go with the motherboard connector
. You don't want to have two switched around and fry your motherboard, or worse.