Dual or Quad Channel

I am working out what to purchase for upgrades on my computer (as far as proc, mobo, and ram goes).

I am deciding between the 2500k and the 3570k. (both under lc with 360 rad)

The only worthwhile reason to go Ivy is the quad channel memory. It would cost me about $170 more (between mobo and ram) to have my desired quad channel setup. That is a tough sell, being I am unaware of the benefit of quad channel.

Ram for dual and quad would be Ripjaws X (2 x 4gb) and Ripjaws Z (4 x 4gb) respectively.

Would the increase in cost be worth the upgrade to quad channel or would the performance increase be negligible?

Oh! I thought Ivy did support quad on X79 chipset O_O

Woops! I guess Ivy doesn't run on X79 at all? My mistake haha. If this is the case, quad channel dilemma is certainly take care of. Thank you sir!

K. I'm starting college this coming fall, so I am still going more budget build. I can't justify the cost of a Sandy E or Ivy E. Thanks for your help sir.

Also, do you have any input as to which processor I should get?

Thanks for the advice on the processor.

And yeah, I know it is cheaper to buy stuff separate, but being I won't be able to use quad channel there will not be a need for 4 sticks XD