http://www.frozencpu.com/products/14918/ex-rad-336/Alphacool_NexXxoS_XT45_Full_Copper_Triple_120mm_Radiator.html?tl=g30c95s161 360mm Rad 80.00
http://www.frozencpu.com/products/14917/ex-rad-335/Alphacool_NexXxoS_XT45_Full_Copper_Dual_120mm_Radiator.html?tl=g30c95s160 240mm Rad 58.00
http://www.frozencpu.com/products/9575/ex-res-156/Bitspower_Water_Tank_Z-Multi_150_Inline_Reservoir_BP-WTZM150P-BK.html?tl=g30c97s165 Internal Res 40.00
http://www.frozencpu.com/products/13148/ex-pmp-132/ Pump 120.00
http://www.frozencpu.com/products/17580/ex-blc-1376/Koolance_CPU-380I_Intel_Liquid_Cooling_CPU_Block_-_No_Fittings_.html?tl=g30c323s831CPU Block 76.00
tl=g30c99s1614 Tubing 26.00
http://www.coolermaster-usa.com/product.php?product_id=2965&product_name=Excalibur%20(R4-EXBB-20PK-R0) 25.00 each
Total = 711.00 (without Fans)
Fitting will depend on how you route things and what brand, color, and angles you need. I added the CM Excalibur fans as a suggestion. I use them on my radiators after trying out quite an array of fans. the reason is that they are quiet and have great static pressure (3.35mmH2O) and move a tremendous amount of air through the Rads. The Cougar
COUGAR CF-V12HP Vortex are about half the cost but still have a decent static pressure and are quiet as well (2.2mmH2O) The number of fans obviously depends on hoe you want to set up your rads (push, pull or both)
The AlphaCool NexXxos rads are excellent quality low restriction and are copper all the way around. (Fins,channels, tanks) They also have a double lipped frame around the perimeter that keeps a screw that is too long from piercing the channels by accident.
The Koolance 380 CPU block is rated the best by just about everyone credible ( I just ordered on myself to replace the 370 I have) I included a silver kill coil. I am a big fan of using only Distilled water and a coil for a number of reasons.
**** You don't have the exact model of your 680's listed but they are non reference cards. you need to confirm compatibility with the non ref ASUS blocks made***
You may run into a lot of warning that are from one end of the spectrum to another. A basic rule is not to introduce aluminum into a copper based loop. A bit of an explanation below.
Copper, Silver, and nickel have very little reactivity with each other (electron transfer) as they are all transitional metals. b) close to each other (atomic weight). So in other words they do not create a destructive environment when used together trying to neutralize their differences in electrons. ( at least they are close enough where for practical purposes (say in our water loops) that they are close enough that a silver coil in a system would be very slow and negligible in a practical application. Aluminum on the other hand, is not a transitional metal and has a lower atomic number (lower number of protons and electrons) and creates an environment of much more active ionization when put in the same environment with transitional metals that are closer in atomic weight/proton/electron count, pulls electrons from the other metals IE damages them. Transitional metals/Abbr/Atomic weight * Silver 'Ag' 47 Transitional Metal *Copper 'Cu' 29 Transitional Metal *Nickel 'Ni' 28 Transitional Metal Non-Transitional metal/ABBR/ Atomic Weight * Aluminum 'Al' 13 Non-Transitional Metal just doing some reading about it quite a long time ago about non compatible metals 'eating/corroding/ ionizing (stealing electrons) or otherwise breaking each other down. assuming you have made sure that you have limited the metals exposed to the water in the loop. 1) If you keep the main components (the vast majority of the metal) it to transitional metals 2) Limit the Non transitional metals in the loop to the Tin (Sn) in the solder. the Copper (Cu) and Zinc (Zn) comprising Brass (both transitional metals) 3) Do not introduce Aluminum to the internal system. The practice would be (for myself) this is what I based my loops on. I use a Silver Coils and Distilled and thats it. I have not observed any ill effects on any part of the metallic loop. I keep an eye on my loops particularly on smaller edges and thinner areas like micro fins for signs of ionization and have seen none sticking to my policy above.
**** This is my findings and research so I am merely sharing the results of putting this in practice in my watercooling.**** .
I don't know how in love you are with your case, but yours is not exactly conducive to a complete bespoke watercooling system so you may want to invest $120 or so in one that is more befitting of one.
Just a thought
Hope that helps. If you want any more help, just holler