most efficient way to make a data store farm?

[lazer_viking]

I've been thinking about making an always-on server for my room mates and I. Theres four of us, each with our own computers and we occasionally watch HD movies on a TV in the living room by streaming them from a computer.
Cumulatively, we have about 3-4 TB between all of our computers. Each encoded movie is about 10 GB, and I would also like to host a library of video games for us to install via the server. (Which as we know
So basically I would like a 8-10 TB local server made up of 1 TB drives with enough SATA ports to double that with 2 TB drives when they become cheaper. I was thinking RAID 5 would be a good choice, since I would think there's a pretty good probability of failure with the number of drives there are.
Any suggestions? The reason I ask is because most motherboards I see only have 4-6 sata ports.. I was looking for a solution that would allow for a ton of headroom if I just wanted to pop in a couple more HDDs every now and then.

 

[Yami]

For that sort of RAID you wouldn't want to use a motherboard's built-in RAID capabilities, instead you'll want a dedicated RAID card with enough ports for the number of drives you want to use. They cost anywhere from $25 to $1,000; the more ports (and features), the more expensive.

 

[Hefemeister]

If you wanted a 8TB raid5 array using 1tb drives you would need 12 drives.

In your situation 2tb drives would be better. For a 8tb array you would need 6 drives.

 

[lazer_viking]

Yeah, I realise that a portion of your total space is dedicated to redundancy

Anyway, thanks for the suggestion of a dedicated RAID card. I can't believe I didn't think of that :/