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Watercooling: The Basics

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AngryAlpaca

Member
Joined
Nov 25, 2003
This is my guide to watercooling, originally posted on Extreme Overclocking Forums. http://forums.extremeoverclocking.com/showthread.php?s=&threadid=71321&perpage=20&pagenumber=2 It got 1100 views in two weeks, so I thought I'd share this guide. Some/all of the suggestions for equipment in other guides are outdated, so I thought this may be useful.

I'm bored, and I know that most people are sick of answering the same answer to the same question repeatedly. First I will start with the basics, and then I will move on to equipment.

Watercooling: How it works

Your processor makes heat. If the heat isn't dissipated, the processor overheats and you are out 100 bucks, approximately. Using a heatsink, the heat is dissipated much better. However, this isn't enough these days to handle the heat loads produced by many processors. So, we add a fan. This is usually enough, if you have a good heatsink and fan. Now, you CAN have a 63 DBa (LOUD) fan to keep your CPU cool, OR you can switch to watercooling and use a 30 DBa or less fan. It also has the potential to cool better.

So, here's how it happens.

A waterblock is placed upon the processor. The point of this is to transfer the heat from the CPU to the water. Water flows through this block, is heated, and then is forced back into the pump. The water is then moved to the radiator, where the heat from the water is transferred to the radiator, and then to the air. A fan can aid in this process. After the radiator, the water will once again be cool, relatively, and then the water is pushed through the waterblock again, and the cycle continues. Watercooling has multiple steps, and thus, it is less efficient than cooling with a heatsink fan. But wait! A heatsink has a limited surface area due to processor weight limits, and so cannot transfer heat as well. With watercooling, the radiator size is limited only by what you can afford. You can use a radiator the size of your house, if you wanted to (You would need a killer pump) That equals more heat transfer area, which equals a cooler processor. A reservoir can be used in a watercooling system, which provides a convenient fill/bleed point, and takes the air bubbles out of the water easily (Air doesn't conduct heat as well as water) It also provides more water, and extra water that may be needed because of water vapour escaping through the tubing. The use of a reservoir has been argued, but I believe it is a good thing to have.

Equipment: What I believe is the best stuff.

Waterblock: Cascade is THE best. However, it costs a lot of money, and requires a good pump. The WhiteWater is the second place block, for the moment. Next in line is the DangerDen RBX. It has a decent price and cooling comparable to the Cascade, but if you have a crappy pump, it cools even better.
The DangerDen Maze3 is when you start moving into the bargain zone. The Maze 3 is better for straight CPU cooling than the Maze 4. *I just read two reviews, and it seem that using a crappy ( <300 GPH) pump, the Maze4 does slightly better* Also in the bargain range is the DtekSpiral, and the SlitEdge from BEcooling.

GPU Waterblock: This is a waterblock for your video card. Dangerden Maze3 GPU (Note that this isn't the CPU version) is the best waterblock for this job. Watercooling your video RAM is possible, but not easy. However, the only retail option for cooling your video RAM, is made up of aluminum.

Chipset Waterblock: There wasn't much attention to my "Which Chipset Waterblock is the Best?" thread, so I will have to be vague about this. They all look pretty good. If you love flow rate, don't go with the Dangerden Z-chip. If you love 3/4" OD tubing, without having to use plastic barbs, don't go with the Swiftech chipset block. If you are really worried about 1/3 of your chipset not getting any flow over, don't get the Dtek 'FSB' Northbridge Cooler. I don't know actual performance, but I these are some guidelines based on design. Chances are good, though, that as the Dtek doesn't hurt the rest of your system (Ie. flow rate, tubing size), performance should be good enough.

Lapping: Lapping is a method of smoothing out your waterblock so that you get better contact with your CPU. To lap, you should get some good quality brand (3M is good) wet-or-dry 600 grit (and possibly higher) sandpaper, a bucket of water with a bit of soap in it, a mirror or piece of glass, the newer the better, and a small damp cloth of some sort. Mark the bottom of the waterblock with an "X" from a felt marker, or, like I do it, squiggle all over, especially in the middle. Find a decently smooth surface, such as a table, and place the damp cloth on it. This is to prevent the glass or mirror from sliding around. Next, place the glass on top of this. Now, wet the sandpaper in the slightly soapy water, as well as your waterblock's base. Place the sandpaper on the mirror, and the waterblock on top. Push the waterblock across the sandpaper, without putting any downwards force on it. Let the weight of the waterblock do the scraping work. After 2-3 minutes, wet the waterblock again, and rotate 90 degrees. Repeat over and over, until all the felt marks are completely gone. It should now be flat. If you are really freaky about the smoothness of this, then you should do this process again with higher grit sandpaper, however, be warned that anything over 600 grit has extremely diminishing returns. Anything over 600 grit probably won't do much at all.

Pump: Eheim 1250, or Hydor L30. Both of these are expensive for what you get. Danner Mag Drives #3 and #7 are good high pressure pumps, but not necessarily more flow, at 0 feet head they have less flow, and they are magnetic so you should keep them away from most of your components, or construct a shield. I couldn't tell you how to do that. The Via Aqua 1300 is a good bargain alternative, and can be aquired for 15 dollars, at some places. It does make noise though, after a while, but this can be fixed. Iwaki pumps are good, high end pumps, they run cool and for a long time, and they move alot of water. On the minus side, though, and this keeps most people from using them, is the size and price. These are both quite large.

Radiator: The heater core from a '86 Chevette is the smallest heater core, and it usually has good enough cooling capabilities. It does need to be modified slightly, and, if this is a problem, you can always buy a DtekCustoms ProCore. Same thing, but premodded, pretty, and twice the price. The heater core from a '76 (Is this right) Chevy pickup with air is a very good heater core, but it's gigantic. It is single pass and so doesn't hurt your flow rate as much. These are the BEST heater cores, but pretty much any will do.

Fans: To cool your non-gigantic case rad, (Open, giant rads can work as passive ones) you should use a fan. 120mm are the best fans, considering that they are more silent, and closer to your radiator size. Assuming that you need 65 CFM (Cubic feet per minute) the best fans I found at sidewindercomputers, where they test the actual sound of the fan, were Sunon 120x25mm Low Speed, at 69 CFM, with a mere 35.5 DBa, as rated by Sidewinder Computers, and the Ultra-Cool 120mm Clear Fan, at 89 CFM, with 39 DBa. Other fans will work too, what you are really looking for is high air movement and low noise, but this is generally hard to find. Ultra-Cool 80mm Clear Fan is the good, silent case fan, in my opinion. A 120mm Evercool aluminum fan is also a nice choice, as it looks good and works good. If noise isn't an issue for the above, get a http://www.frozencpu.com/cgi-bin/frozencpu/fan-22.html and 80mm Tornadoes for your small case fan. These are loud. Don't say I didn't warn you.

Reservoir: Tupperware, a knife, and hose barbs. Bay Reservoirs supposedly leak, and that is not good.

Tubing: You should buy 1/2" ID (Inside diameter) tubing, of some sort. Tygon is flexible and doesn't kink easily. It costs 2.90 USD per foot, and as such probably won't be feasible for many of you. Next in line is Clearflex tubing, at 1.50 USD per foot, it is still fairly good, about just over half the cost. I got my 1/2" ID 3/4" OD tubing from Home Depot, for approximately 1.00 CAD per foot, and it works great.

Clamps: These are necessary. Worm drive clamps are cheap, good, adjustable clamps, that come in pretty much any size. You need a screwdriver to tighten them. Specially made hose clamps also exist, but these appear to be crap.

Cooling Fluid: For best heat transfer/heat capacity, nothing beats pure water. However, it is best to add 5% Water Wetter to prevent organic growth and corrosion. Anti-freeze sucks, for those who were thinking about it. You might need to use other liquids if you chill your water, but I wouldn't worry about it, seeing as you are perusing my Watercooling Basics guide.

Water chilling: Now we are getting out of the basics, and more into the advanced usage of a watercooling system. Chilling is to make your water cooler than its surroundings. This is usually done with a phase change unit, such as a fridge, air conditioner, or dehumidifyer. DO NOT USE A MINIFRIDGE! THIS IS ALWAYS THE FIRST QUESTION EVERYONE ASKS! It will not hold up to the load. An air conditioner over 5000 BTU will usually cut it, and keep your water nice and cool. A 40 pint dehumidifier should also work.To get this to chill your water, you should gut it, and put the cooling coils from the unit in your reservoir, or, build a new reservoir. This will probably require you to build an out-of-case place for your stuff. Now: That's the easy part. Now, you need to condensation proof your motherboard. You need hose insulators, and something to insulate your waterblock. While chilling, the water may come to a lower temperature than 0 degrees Celcius. For those of you who don't know, that is frozen water. So, we need to add something with a lower freezing point, such as our good friend alcohol, or antifreeze. However, antifreeze has TERRIBLE cooling capacities, so alcohol/water or just plain windshield wiper fluid is what you should probably go for.

TECs: http://forums.extremeoverclocking.c...&threadid=36894 This guide will give you all the information you need, about the actual TEC. It doesn't say how to cool the hotside, other than water, and it doesn't recommend parts. Swiftech has a very easy to use TEC waterblock, the MCW-462UHT. It has 1/2" ID barbs, so the fact that it is Swiftech is nullified. The DD Maze 4 is a good waterblock for TEC use, and the DD coldplate clamps to the top for good heat transfer between Coldplate, TEC, and waterblock, but it isn't as easy to use as the Swiftech. Use a 226W TEC to get nice temperatures, but for a quick, easy improvement, I would just use a 160W or so TEC. You won't break the bank buying a PSU, and you won't have to go second-hand. You will still get 10-12 degrees better, if you have decent cooling for the hotside. Some people don't think you should have a TEC directly on your processor, but, some people think water cooling is a bad idea. I'm not saying that they are right or wrong, I'm just saying they really aren't too extreme. You will need to protect from condensation, and, using closed cell foam, or neoprene, this is relatively simple. I don't want to complicate my life too much by explaining, so I will just provide this link: http://www.swiftnets.com/socketsealing.htm I trust Swiftech enough to let them condensation proof it. IF YOU GET A TEC WITH BARE WIRE LEADS, MAKE SURE YOU PLUG IT INTO THE RIGHT PLACE! IT ISN'T ORANGE TO ORANGE AND PURPLE TO PURPLE, LIKE IT WOULD BE WITH MOST WIRING, IT'S PURPLE TO BLACK AND ORANGE TO YELLOW! Personal experience.

TEC power supplies: It's simple, really. There are Meanwells. Meanwells are not great. Sure, they fit easily within your unmodded case, but they run hot, and they cost $120! 120! Then, after you've realized that with the cost of a watercooling system, TEC, and a Meanwell, you could've just bought a Prommie, you decide to go with a regular power supply. Good regular power supplies, that provide enough amps, are good TEC PSUs. You should use a 25amp on the 12v line for a 226W, and at least an 18amp one for a 160W unit. Much weaker of a pelt, and there isn't any point. On the minus side, you will have to mod your case, or put your extra PSU externally to fit it. ATX PSU's won't start normally unless the motherboard is connected, but that it avoidable. Take a paper clip, and stick one end in the green wire thing. Put the other end in a black one. It should now start. You might want to tape up the paperclip so you don't get shocked, at some point or another.

One more thing: DO NOT BUY A KIT! I WILL TRACK YOU DOWN AND BRAND "MORON" ON YOU IF YOU BUY A KIT!(Don't take this threat seriously)(Kits don't allow total customization, with one exception, and they all cost more than the component parts, with no gain, except a minor amount of temporary convenience.)

That's pretty much all there is to it. If I made any errors, or omissions, do not be afraid to let me know.
 
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Welcome to the forum. This forum also has a guide but you explained a couple extra things that might be helpful also. I especially like the RBX comment. I guess we'll see if it is true when some real numbers come out ;)

BTW: your extreme forum links don't seem to work.
 
We've had this discussion... There has only been one or two reviews. It is still VERY questionable, but, based on present knowledge the RBX is better. The only review I can remember is the liquidninjas roundup, which places the RBX slightly behind the Cascade. Good news: Joe Citarella is doing a review of it soon.
 
It's beaten it in one review, that's better than what the WhiteWater has done. However, in my opinion, the difference is negligible at this moment at time. I'll change it if I feel it necessary after Joe's review.
 
Godfather84 said:
"DO NOT BUY A KIT! I WILL TRACK YOU DOWN AND BRAND "MORON" ON YOU IF YOU BUY A KIT!"

Thats Funny :lol
The point about avoiding kits because the convenience factor isn't worth the added costs and lack of customizability could have been made without that. I didn't buy a kit and I'm not likely to ever do so, but I'm not going to brand people as morons for it. I can let others make choices that I wouldn't without getting on people's backs. Btw Godfather84 that link in your sig isn't allowed, you'll need to remove it.
 
That one line has created more controversy than anything else in that guide. I'M KIDDING.
 
AngryAlpaca said:
We've had this discussion... There has only been one or two reviews. It is still VERY questionable, but, based on present knowledge the RBX is better. The only review I can remember is the liquidninjas roundup, which places the RBX slightly behind the Cascade. Good news: Joe Citarella is doing a review of it soon.

Many people have proven flaws in Liquid Ninjas review. I wouldn't trust it...I wish I could find linkage to it but I can't. I'll wait till Joe reviews it before I take an RBX over the WW anyday. We'll, if the WW lapping has been fixed.
 
AngryAlpaca said:
That one line has created more controversy than anything else in that guide. I'M KIDDING.
I know, I'm just using an ounce of prevention to make sure I don't need to use a pound of cure. I've seen humorful jabs like that turn into flame wars.
 
Well, I don't like the accuracy of either of the RBX reviewers. But, they're the best I could find.
 
As of now i dont believe there is any concrete review on how the RBX is doing so IMO, it is hard to compare it to other blocks such as Cascade or WW, which have been proven to be a good performer. However, I do believe that RBX is a good performer but its too early to make any comparsion with other proven blocks mainly because it lacks any solid evidence.
 
The Whitewater is back in second place, next to the Cascade, until further testing is done.
 
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the pickup heater core you are mentioning is an early 70's chevy w/ air (ie 1970 K10 w/ air ... GDI p/n 39-9090)

water wetter seems to cloud tubing so anti freeze is being suggested instead for corrosion resistance and protection from algea growth

bladerunner happily cools the ram on all of his video cards

it has also been mentioned that wrapping electrical tape around the tubing ends before you put the hose clamps on will protect the tubing not allowing you to crush it when you tighten the clamps
 
I've never seen a crushed tube... Anything I've read so far says that anti freeze sucks, for most purposes, except preventing freezing. Clouding tubing: As in leaving the slimy residue? That shouldn't happen if you put the right amount in. What's the method of cooling the video RAM? And is there any point? Don't passive RAM sinks work well enough?
 
personally i've only had cheap homedepot brand tubing get 'crushed' but more like mutilated.. but still worked. good quality tubing is (like from usplastics, clearflex, etc.) is damn good and i've tightened a clamp enough to close the seal it (damn good).
As for antifreeze, i don't think it sucks
maybe at 100% uh.. YEAh! but 10-20%, does a good job.
and doesn't stink
and only leaves a residue on cheap tubing (vinyl homedepot ****a)
and it doesn't cloud tubing (in my like 20th refillup of experiance)
and it tastes bad and is toxic.. which makes my biohazard grill just more fitting. :D

as for cooling video ram.. meh.. ram in general i don't like cooling
video ram.. i guess its an exception because of lower memory timings.
if u have sufficient airflow in ur case, passive ramsinks are more then plenty.
seen someone peltier cool their video memory.. no improvements
but if it gets hot, might as well cool it right?
sometimes improve stabilty too if its getting too hot when overclocking..
depends or ur gpu though..
 
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