Fuzion V1 vs V2 & loop capacity Q's

[arnemetis]

Hi Everyone!
I'd like to address some questions with my upcoming loop in one thread.

1)First, I already have a fuzion v1, pro mount, and nozzle kit I purchased from petra's when it was on sale in anticipation of my build - but now the v2 is out and I'm wondering if it will be worth selling the unused v1 to pick up the new v2 with quad plate. Reviews generally look pretty good but would the added flow benefit me more? Would I only see a degree difference with such a full loop?
2)Second, I need some help figuring out how much heat my loop can actually handle, which will sadly decide what graphics cards I get. I would like dual gtx 280's, but may have to settle for dual 260's due to the heat. My best guesses by looking at Martin's flow chart (2.01GPM w/ v1+quad nozzle, 1.95GPM w/ v2 and quad plate) and thermochill's data is that I should be able to handle ~530 watts of heat.

Hardware:
dual ddc 3.2 18w pumps both with petra's tops in series
PA 120.3 with 6x medium yates from pts (stated cfm was ~70, testing here showed ~50cfm actual)
dtek fuzion v1 or v2 on a heavily overclocked q6600
mobo block that comes with evga 780i ftw (when its finally released)
dual 280 gtx blocks from ek
swiftech microres & 7/16 masterkleer tubing

I'm going to cut this one off at the pass and say I have no interest in setting up a two loop configuration. Let me know if any more information is needed, and I'll provide it. Thanks in advance for any suggestions!

[arnemetis]

Nothing?

[MomijiTMO]

Hmm I would consider 2 loops as you are buying 2 pumps. The reason is that the 260s will be quite happy running in the 50s whereas your CPU would be much happier if it were in the high 30s. I would consider buying a MCR220 [cheap] to cool your cpu and use the 120.3 to cool your hot SLI set up. Of course you could chance the rads if you believe your cpu is that hot [which it isn't but spoiling it isn't bad either].

[arnemetis]

Changing to a two loop configuartion isn't possible. I will have a single PA 120.3 with 6x fans to push a good amount of air, and dual pumps to get the GPMs up there. There simply's isn't room and I refuse to use an externally hung radiator again.
Would appreciate some input on the v1 vs v2 issue though. My best guesstimates so far are the quad putting out at most 200w of heat, the chipset 30w, and the gpu's around 150 each - was hoping to get better than guessing numbers on the gpus here at least Seems I have a habit of always posting questions noone knows the answer to/wants to answer in forums nowadays

[Polizei]

Push/pull fans doesn't increase the cfm figures as much as it increases noise.

The Fuzion V2 is more restrictive than the V1... that's how they get a tiny bit more performance out of it. The pins are shorter leaving less room for the water to flow, but the added restriction increases water speed so it transfers heat better. It still flows great, but the V1 is still better in terms of flow.

I hope you have some medium speed fans or faster... ~450w of heat out of that PA120.3 won't happen with low speed fans.

[arnemetis]

In my op I stated that I would be using medium speed yates, and even 3x fans should give me 450w of cooling easy, with 6x i should be able to get to 500-550w at high flow. I've tried out the fans at 12v and they are plenty quiet, even agaisnt the rad, so i'm not concerned. I guess there's no easy answer for which is better - the better flow of v1 or the better performance of the v2?

[Martinm210]

Don't forget those heat dissipated curves are based on 10C deltas which is really only average performance for watercooling these days. It's not too hard to reach 5C and less deltas when designed right. I wouldn't worry about flow rate difference it's negligible. The V2 should give you something, but I've heard at least one person tell me they weren't able to measure any difference, so it's one of those close things that may or may not amount to any measureable difference depending on what you have to use for measuring. Push/pull with shrouds on both sides will help...

Add in a PA120.1 somewhere if you can, then you'll at least gain that much more surface area. Restriction is so low on the PAs, it won't affect flow enough to even worry about.

[arnemetis]

Damn case is so tight with stuff as it is, and I bought a new stacker which seems so huge when empty Unfortunately the 120.3 will have the fans stuck right against them, no room for shrouds or even neoprene gaskets... I'll review my design but I don't think i have room for another rad So if I can't fit anything else, I'm stuck with the single 120.3 loop - am I screwed with a q6600 and dual gtx 260's in it?
P.S. Thanks to everyone for their help, and lucky me to have Martin grace my thread with his wisdom

:edit: Well if i really wanted to, I COULD add a 120.1 to the mix right at the back 120mm exaust fan (I have a stacker stc-t01 case), however god help me if i ever want to remove components like my motherboard...You don't seem to have the 120.1 in your testing, but even adding another 120.3 would only incur a 0.04GPM hit, so I'm sure i can live with it. I'll re-check the case this weekend and see if i can fit it in there. Will this really boost my cooling capacity, because it sure will be difficult to work with my case with a radiator in the way?