[quote=@Meta]
<Snipped quote by DarkwolfX37>

Because MC is terribly programmed; that can probably be fixed by allocating more. If not, 16 gigs won't make it all that much better. 16 is recommended because it's future proof, but 8GB won't hinder your performance for at least two years, probably closer to five. If you want to spring for 16, it's good future proofing, but that's about it.
It's difficult when I'm not sure what you're doing. If you're upgrading, I have to make sure that what you're getting is compatible with your motherboard. If you're building from scratch, then you get to look for the cheapest and best parts.
I didn't understand this last sentence at all.
[/quote]

I'm trying to upgrade but if I build from scratch and the harddrives are compatible then fuck it. I just want a better computer so I can play new games. 
And with MC I've allocated all 8 and still had problems.