RAM triple channel/single stick and other lovely stuff

G'day.
This is just a quick question, because in my rather sleep deprived state none of the answers I can find via Google is really satisfying me.
I suspect one of my RAM sticks is going bad, or is already gone. Heavy load simply kills my system.
Anyway, I was planning to upgrade from my 6GB anyway, so I might just as well do that now.
My MOBO is a Asus P6T SE, which means I'll go for a triple channel setup. Currently using 3x2GB.

Now, I can't find a decent offer of RAM I like for a decent price over here. I have, however, found an offer I like for a single stick.
If I simply buy three of the exact same sticks and put them in the right slots and all, they will work as triple channel, right? Or is there any marked difference in the way they are built?

And just out of interest, if I went overboard and filled all six slots, would that mean I'd have two triple channel setups going on? Or would that negate the whole benefit thing?
Not that I plan to do this, but it crossed my mind.

Thanks in advance.
I realise the question is kinda trivial, but it just nags me and I couldn't find a nice answer specifically to this question.

Yes.

If you stick 3 identical RAM sticks in the same color slots, you'll get x-channel depending on how many your motherboard is capable of.

Thanks, exactly what I wanted to hear.

While I'm at it, how noticeable is the difference between for example CL9 and CL7 really? I can't imagine any real difference in performance outside of benchmarking or trying to squeeze the last few FPS out of a game.

You won't gain much of anything. FPS is limited by instructions processed as opposed to RAM access.

Like I said, tired. You know what I meant.
But yeah, answered that for myself via Google.

Thanks though.