Should be fine, you might/more likely will have to manually set the memory speed, timings etc in BIOS though to run at 1600MHz. That Intel spec sheet is just giving you the standard supported memory speeds, a lot of the time anything about 1333MHz will need to be manually set (the system will boot at a lower memory speed/higher timings).
Why would I have to manually set it when the memory is 1600MHz 9-9-9-24 at stock?
Because the CPU doesn't offically support that memory speed. So it will boot up with your memory sticks at a lower speed like 1333MHz and then that is when you can go in and set the memory speed and timings to the proper specifications of the memory sticks.
This is a very common occurance for basically everyone who has bought memory at 1600MHz or more, i actually had to manually change the memory speed and timings for my 8GB Corsair Vengence kit (1600MHz) as well. This because my 1055T does not offically support speeds higher than 1333MHz.
This is changing though, for instance the Core i7 3770K offically supports 1600MHz memory out of the box. But again anything above that will need to be manually set.
So I don't necessarily need to change it to 1333MHz, but to get better speed I ought to change it to 1333MHz and change the timings anyways. Am I right?
If so, how exactly do you do RAM CAS over/underclocking?
No the system will boot at 1333MHz already when the new sticks are installed, so you'd just need to go into BIOS and get the speed to 1600MHz. You will more likely have to set the memory timing to 9-9-9-24 manually as well because it might boot at higher timings (it's better to have as low timings as possible).
Bare in mind though that memory speed really isn't an important factor in most software, you never notice a difference between 1333MHz and 1600MHz in things like gaming or borwing the web.
Just wanted to say that this thread has helped me. I am building an HTPC with a H77M motherboard that can support 1600MHz, and the i3-2120. I was wondering whether to get 1333MHz or 1600MHz and step it down, apparently I don't have to; I just need to manually set for 1600MHz. Thanks CPdude55