Originally posted by: ned4spd8874
Does processor matter for a NAS? I have an i7 btw.
The processor in what? Your computer or in the NAS?

Any NAS appliance will have it's own dedicated processor inside. The processor in your computer doesn't matter. Your network transfer speeds DO matter, though. But for the typical home user, your typical 4-port 100MB switch/cable modem will do fine.
If you want to start with 2 drives (I'm assuming they are the same make/model/size) and work your way up, that's fine. But you'll need to purchase a 4-bay (drive) NAS.
What's your budget? 4-bay NAS appliances aren't cheap. Expect to pay $300+ for a decent one, and that's without any drives.
I've had my D-Link DNS-343 for about two months now with 3, 500GB drives in a RAID5 array. I like it...so far, so good.
You can turn an old PC into a "NAS" with minimal effort. The main issues for me were an old tower taking up space and the electricity it was using. Used to be in Ye Olden Days if you wanted "a file server" you had to keep an entire computer running 24/7 just to do that. Motherboard/videocard/fans/etc running 24/7. All modern NAS appliances can be set to go to sleep after x-minutes of inactivity. In that state they draw minimal juice.
It all depends on your needs and wallet.

If you don't want to spend that kind of dough and have have an old PC lying around (even a Pentium 3 makes a fine file server) that may be the way to go.