2 loops 1 pump

[Gabriel5]

Current loop: RX360 RAD, NB, HK 3, 4870x2, D5 pump.


I have a question for the great ones regarding the feasibility of splitting up a single loop to run as two loops with only one radiator and pump. I was planning on buying a Primochill Typhoon III reservoir, which allows a single D5 pump to power two loops that feed out of the same reservoir. Here is my question:
Do you think it's feasible to run a single loop through the radiator and a second loop through everything else?

My reasoning is that if all the water in the system is the same temperate, splitting up the loops will decrease overall resistence and make the pump more efficient, while maintaining cooling performance.

What do you think?

The Typhoon III:

My system right now

 

[sok0]

Umm, that sounds like 1 loop to me if they share the same res/rad/pump. Regardless of how you separate the tubing, a hot cpu will dump hot water to the rest of the blocks. 2 loops consist of 1 pump/res/rad for each loop.

 

[Shiny]

To answer your question - while you most definitely can do that, it probably wouldn't give you much of a performance benefit (more likely the opposite). The reason I suggest this is that while you definitely are gaining flow, you'll be losing actual cooling.
The one loop will go through very quickly and be cooled by the radiator. Meanwhile the other loop will go through and be uncooled. The water gets mixed in the middle. The temperature will even out between the two loops. However, the temperature average between the two loops is likely far higher then you would get if all the water went through the radiator. Unless your two loops are extremely restrictive, it doesn't seem very likely that the added flow rate would be of greater benefit to your system.
Judging by your system specs listed, I'd say you're pump probably does the job fine as is, and splitting the loop to decrease restriction won't give much added benefit.
On the other hand, you might be able to split the loops through the blocks (I'm assuming you planned one loop for the cpu and northbridge, and the other for the gpu?) at 3/8th's meet at the radiator with a T juncture (sending both 3/8ths into a single 1/2 inch fitting) and then send another 1/2 line back the radiator. You'll gain some restriction from the splitting and fusing of those 3/8th lines, but it'll be offset with interest by that dual loop.
One word of caution overall though - those typhoons had some serious trouble with leaking on the first round through. They just rebuilt them, and some of the guys involved even left. You may want to wait a bit to see how quality control is on this go around.

 

[Gabriel5]

Thanks for the great feedback. I'll definitely take that into account. I think I'll probably just do a regular loop...
From what I read the problems with the typhoons was really just a problem of using glycol, which also happens to be in most commercial solutions, but I just use distilled water. I didn't realize there were other problems, I'll have to be cautious...

As an aside, I'm very happy with the cooling performance I'm getting now, particularly from my radiator. This is my first try at water cooling. When I asked others what kind of cooling set-up I needed I got plenty of more expensive suggestions, including additional radiators and pumps. But I have to say it does a great job. I haven't really tweaked with it too much yet, but with my vcore sitting at 1.29 at 4.GHz, it barely gets into the 60s on a load, and the 4870x2 stays in the 30-45 range.

At any rate, I'll probably try it out in the next month and I'll post the results.

 

[bigbadgreen]

I have a suggestion to slightly modify that design to setup a cheaper and more efficient cooling system. I haven't done research on that res but from what I understand it looks as if there are two inlet and two outlet barbs allowing for two loops. You ask about only running one radiator. This can work but your overall temps will be slightly higher because half of the system is not being cooled and has to be cycled through the loop with the rad before it is cooled. So if you wanted the coolest loop you would be forced to use two rads, one for each loop. Without being sure of how that res works I say there is a way to only use one rad. at the end of the loop cycle, right before the coolant enters the res install your rad. plug off one of the return holes to the res and install a Y fitting to flow all of the coolant through one rad and then dump it into the res. You would have to do it here because trying to push it through one rad right after it exits the res would lead to uneven flow and one of your loops has a chance to seriously overheat from coolant not flowing, it would give preference to the loop with the least restrictive flow.
To make it even better you could plug both return holes and install your own larger return so it doesn't bottleneck there. although having the coolant spend a few extra second in the rad would make it more effiecient at dissapating the heat. Just make sure it doesn't bottleneck so much as to starve the pump. although it shouldn't once you get the system flowing.

So with some simple modifying you could run two loops with one rad and it would work quite well as long as your rad could keep up with the heat.