Couple of things first.
What case do you have now?
Whats your objective, cool or quiet or both?
What sort of use does the system get?
What sort or ambient temps do you have?
Do you care what it looks like in the end or do you have aesthetic requirements?
You say budget not really restricted "as such", do you have a budget in mind? Just asking because really the sky is the limit when you are talking about the best watercooling cases costing up to £3-400 before you even add the watercooling parts.
Of course you can do it cheaper, depends how handy you are with a hacksaw, dremel and how comfortable you are cutting your case up.
That CPU and two 680s you would need at least a 360 radiator, possibly with a secondary 120 or 240 radiator if you could fit one.
Just about any of the larger cases would work, Elysium, Bitfenix Colosos or Shinobi, The Corsair 800D is doable but might need a bit of modding to fit a 240 as well as a 360 but a 120 on the rear exhaust would work.
Generally thicker rads work better with low speed fans, but thinner rads offer superior cooling with high speed fans (plus the requisite noise levels)
Budget for a decent pump, like a Liang D5 or DDC 18w and budget for either an aftermarket top (if using a separate res) or a top with res if you want to go that route. Some find it neater to use a bayres, some like a separate tube res. I have no preference, depends really on space/cost/convenience.
The rest is down to personal preference, tubing size, colour, fittings brand, compression or barbs, its just what you like to work with.
Oh and read, there are lots of good FAQ's and sites around. This very board has a great sticky about watercooling, and there are other great sites such as
XstremeSystems LiquidCooling and lots of testing done at the likes of
Martins Liquid Labs and
Skinees
And last but not least the OcUk
Project Logs subforum is pretty awesome for ideas.
Hope this inspires rather than scares you off, but once you get started its a bit of an addiction. Just don't try and watercool the cat
