I cannot wait to get the money together for benching, how much dry ice does say 2 hours of benching take?
I get mine at the grocery store for a $1.09 a pound, 10 pound blocks of it. Keep it in a ice chest and tape around the seam with duct tape so it doesn't evap as fast. When you hit it with a hammer it shatters real well, get a big spoon so you can use the "Sand" thats created form breaking it. I break some of it up and then put what I'm going to use out in a 6 pack cooler and tape the big chest back up and throw some blankets over it to help insulate it. I use some channel locks to crush and smash some of the pieces in my smaller chest as I go along.
It can burn you so don't hold it in your hands to long, it pulls the moisture out of your skin its so cold.
I use a 1/4" x 10" brass rod to stir it and punch down pieces that get stuck. Don't do that when its running, wait till its off and your clearing CMOS.
A shot glass is good to measure out your acetone with to, you have to be careful and not add to much or it can spew out all over everything. I put about a ounce in to start it off then some more in a hour or so, keep watching temp's and you'll know when to add ice or acetone, if you add ice and the temp's don't drop in a minute or so you know its time to add a little more acetone. Acetone has strong fumes, stay well ventilated or it can make you sick. It can flash to so keep it away from sparks and flames. I use a little plastic funnel to add acetone with, then I flip it upside down and set it ove th etop of the pot so air doesn't hit it as much. Keep plenty of paper towels on hand.
You'll want more then 2 hours worth if you pushing it, I'd at least get 20 pounds, that will last a day and evening of clocking.
Know your board and ram likes and dis-likes before you use the DI, you want to be able to push it to your max OC from the start and push it from there, saves time that way.
Its fun and pretty easy once you get the basics down, and you can only learn that by doing it.