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Liquid Cooling More than One Component?
static0verdrive asks: "I am new to liquid-cooling, and I have designed a system for use in a micro-ATX OpenBSD server, with the following layout: Fillport > Reservoir/Pump > Y Split (one to CPU and the other to chip-set) > Y Reconnect > Radiator/Fan > Back to the fillport. I don't like the idea of having the hot coolant coming from the CPU going directly to the chip-set, hence the Y split. Could this split cause any problems? Would there be a difference in pressure (considering the CPU is most likely a lot hotter) that could cause an issue? How would you handle liquid-cooling more than one component? What if I wanted to cool 3 components, such as in the case where I add a video card to this setup later on?"
Jean Gallier at UPenn has a lot of stuff about this on his webpage: here
I've looked into liquid cooling for a machine, but haven't done anything yet. From what I've found out, an ideal solution is to go reservoir->pump->cpu->video card (if doing video card)->north bridge-> radiator->reservoir. You get max cooling this way. Introducing a Y splitter introduces another connection (in which liquid can leak) and split forces of liquid. The liquid will take the path of least resistance, so you might not get max colling that way. I've found that Systemcooling.com has a wealth of information. You might want to pose this question on their forums, as they do more liquid cooling and have people who have done many systems.
You can find some really good advice and watercooling guides, like this one: http://forums.bit-tech.net/showthread.php?t=99891.
The bottom line on your waterloop, in my own experience, you'll find that the order in which the water is flowing results in negligible water temperature increase/decrease.
I have two machines WC'ed, a P4 (pre-prescott) and a Dual Xeon. The order of the loop for the P4, pump/res> radiator > CPU Waterblock > GPU Waterblock > Flow Indicator > Pump.
The P4 only gets to about 90F during heavy gaming sessions (ATI X800XL). Then again, I have a triple 80MM fan radiator. Your results may and will vary.
Don't use "Y-splits" to redirect fluid. I understand your concern that you don't want hot parts connected in series but a series connection is superior to a parallel setup. The resistance overhead for a series setup is negligible. Also, was previously mentioned, it is more advantageous for you to minimize the amount of junctions and thereby increase the reliability of your setup.
"I am new to liquid-cooling, and I have designed a system for use in a micro-ATX OpenBSD server, with the following layout: Fillport > Reservoir/Pump > Y Split (one to CPU and the other to chip-set) > Y Reconnect > Radiator/Fan > Back to the fillport. I don't like the idea of having the hot coolant coming from the CPU going directly to the chip-set, hence the Y split. Could this split cause any problems? Would there be a difference in pressure (considering the CPU is most likely a lot hotter) that could cause an issue? How would you handle liquid-cooling more than one component? What if I wanted to cool 3 components, such as in the case where I add a video card to this setup later on?"
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Splitting the main(Y-split) to cool several devices is generally not recommend over cooling multiple components in serial.
Most people go: Pump->CPU->radiator->reservoir
some people go: Pump->CPU->Video GPU->radiator->reservoir
and very few people go: Pump->CPU->Video GPU->Chipset->radiator->reservoir
( or even Pump->CPU->Video GPU #1>-Video GPU #2->Chipset->Memory->radiator->reservoir)
As you add more and more stuff to the circuit, you'll also need a bigger pump, a bigger radiator, and you'll have to seal the connection points more carefully to gaurd against leaks resulting from higher pressure. It's the general consensus that splitting the coolant in a parallel fashion like you're describing is less effective than connecting the components in serial. The primary reason is that flowrate X volume is king in water cooling...with a Y-split you're cutting your CPU water cooling volume in half, and probably restricting flow even further with narrower tubing. Also, pressure drop in the system is a function of how much tubing you use. More tube, less pressure. People have tried this before...and their results weren't comparable with serial.
I'm assuming you want to water cool so you can overclock. If this is so, then you need to prioritize your CPU over everything else. If you don't plan on overclocking and just want the silence, then you're still better off using serial because it's cheaper and safer(less connection points means a lower leak probability).
Don't worry about warm water returning from the CPU and 'heating' the chipset. Fast flowrate and the high heat capacity of water keep this from being a problem. Generally the water temperature across the entire circuit is nearly homogenous(maybe 1-2 degrees difference).
To learn more:
1) Goto http://www.ocforums.com/forumdisplay.php?s=099a5c
2) Spend at least 2 hours reading the stickies etc. (or register and ask your own question, the folks there are very knowledgeable.)
Good luck with it!
The government has a defect: it's potentially democratic. Corporations have no defect: they're pure tyrannies. -Chomsky
..maybe check out HP's new air cooling rig instead.
hi. I'm a mechanical engineer (who loves to tinker) and has used watercooling. I'm going to suggest a few steps to help you see that your system is successful. (I'm not going to use any numbers or calculation, because I'm very lazy: 1) I did the work once for my own systems and found that the work was overkill, 2) water can carry more heat than you realize 3) I'm lazy.
...And that I'm lazy?
1. Relax, be lazy and have a beer. You're dealing with (I think) a server in your home that is probably going to remain lightly loaded. Even if you expect heavy loading, you still need to relax.
2. Please know that the major reason to use water is that water has a MUCH higher heat capacity than does air. Another good reason is that water conducts heat better than does air.
3. What you've already done is probably good enough. I use one water pump and four manifolds to feed three systems. (The water pump has a simple backup, although this is manual for now. I've not taken the time I need to learn how to design my vision of a good backup for it.) I don't overclock, but I'm lazy and don't want to deal with the hassle.
4. You're talking about pulling from the system a maximum of probably 150 watts, assuming that your mATX system has a VERY high load on it. Unless you live in the midst of the mojave, you won't have any trouble pulling sufficient heat from the system. Remember that your car's cooling system can remove MUCH more heat. (A note to the pedantists: SHUT UP. I know that there are differences and I'm inimately familiar with the differences, but the analogy is good. Based on the scant information the poster has given, he's already well-covered.)
5. TEST IT. Stop worrying, turn it on and see what you get. If you don't (as I don't) want to bother with lmsensors, (or the BSD equivalent), turn it on, load it for a few hours, reboot it and see what the BIOS tells you the temperatures are. If everything looks good, then you're golden. This is not a good design/testing methodology, but you're not designing a nuclear reactor which needs perfect redundancy and endless, constant tests to ensure that everything is operating perfectly. Keep an occasional eye on your water pump (there are several different types of flow meters available) and a very lax eye on temperatures; doing both of these will keep you sufficiently covered. (By the way, your sytem will still probably circulate a very small amount of water even if the pump fails. This depends on a temperature and gradient difference, though.)
p.s. I'm assuming that you're not overclocking your system, nor operating in extreme environments.
p.p.s. There are sizable holes in my advice. If you're looking for specific numbers, I'll charge you reasonable fees for reasonable consultation. Feel free to contact me if you want to pay my inflated rates.
p.p.p.s. Have you noticed yet that I like bullets of one kind or another?
my last little bit: my point 5 is probably the best of what I've said. Turn it on and see what you get. Edison didn't have any results until he provided current. If you turn the thing on and it doesn't work out well, you can turn it back off in a few minutes and probably still be just fine. Remember, though, that most BIOSs can be configured to shut down the system if the temperatures get too high, providing enough fail-safe to determine that everything works.
A parallel tubing configuration will always be superior to a series configuration (unless you are using a positive displacement pump for some reason). IF you have a method to balance the flow correctly to each component (such as throttle valves). The reduced flow resistance will allow the pump to operate at a higher flowrate and will make heat transfer in the radiator more efficient. This will reduce the outlet temperature of the radiator, supplying cooler water to each component. This makes all your components run cooler and also reduces the power usage of the pump.
If you don't have a method to correctly balance the flow then your best bet is a hybrid series-parallel configuration. The best solution will depend on the heat load of every component you want to cool and the physical characteristics of the pump and radiator.
My current loop is as follows:
Athlon MP2800+ -> Athlon MP2800+ -> AMD 762 Northbridge -> FireGL X1-128 -> Koolance 2 DIMM RAM cooler-> Reserator.
Once the temperatures reach steady state, the difference in temperature between any two points in the loop is less than 2 degrees C. In doesn't really matter how much water is circulating or how fast (these do matter though, in determining how fast the steady state can change when a cooled component suddenly changes its temperature). What really matters is the surface area of your radiator, and the airflow over it's fins.
Under full load, on a 30C day, the Reserator is very warm to the touch. I can drop the temperature to below room temperature by putting a fan behind it. Whatever temperature the radiator is at is the temperature the blocks are at (at steady state conditions).
If you want to cool more components, you don't have to fill up your case with parallel cooling loops. Instead, add them in series and add another radiator is series also. You only ever need one input hose and one output hose piercing the case. The Reserators work really well for this, since you only need a pump in one of them. The other(s) are just extra surface area.
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