Because, good sir, Minecraft eats your RAM up like a jar of cookies. That is why. Its also very CPU intensive, and Ill be damned if I settle for less.
DID YOU ACTUALLY BUY AN i7 AND 16GB OF RAM FOR MINECRAFT
WHAT HTE forget
seriously, you should cancel your order and save some money
minecraft doesnt need more than 4GB of ram. it doesn't need anything above a 100 dollar cpu. you just blankly wasted money.
did you at least order a graphics card?