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3/8 or 1/2 hose?

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Jun 19, 2001
I going to start assembling my parts for my water cooling project. I see some using 1/2 inch and some using 3/8. I want to use 3/8 do to its what I have available and I have a ton of it and a ton of 3/8 fittings. My question really is do you guys feel that 3/8 hose will cool adaquitely?
I used 1/2" but only because I had already built my rad to use 1/2". I am using a Eheim 1250 pump and Gemini High Volume Block. With this setup it only delivers 60 GPH going through the block, even though the pump is a 317 GPH pump. I have about a 10" rise and this does have an effect on output. Hoot is using 3/8" tubing with nearly the same setup and our C/W is the same.
Wow, that’s a nice looking setup you have there Dodge. I wish mine looked that clean and open. :D

*edit* Arrgghh!! No fair. I just noticed that your mobo power connector is way up there by your W/B and out of the way and out of sight. Mine is right there by my IDE connectors talking up space and looking ugly. Grrrr
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Just curious Viper. Having your radiator there. Does the fan push in or out the front. The reason I ask is because if its pushing out, is cooling the water with warm case air. Or if its pushing in the heat is exhausting into case? Help me understand before I put my rig together.
To answer the original question, I am now running a xp1600 at 1.73Ghz 2.2vcore using a maze2 and 3/8 line. It should be noted that I use a bong as well.
Customrig, I have a T inline with the T line going to the top of the case. At the end of the line is a fitting with a cap. Just unscrew the cap and fill the water.

CSaddict, Air is being pushed into the case from the front fan. The rear fan is pulling air into the case. Push/Pull format. The two rear fans are exhausting the air out the case. I have a small amount of positive pressure in the case.
3/8 hose will work just fine ! I have found that a higher capacidy pump 9 that is a pump with a higher flow rate actually raised my temps by about 5% The theory is that the water moves too fast to absorb all the heat it can. I find a flow rate of about 100 gph is perfect.

!/2 inch hose works great too but you dont need to use it.

Picture this, alot of water coming in (ex: my 3.5"x4.0" block with three inlets and three outlets) on a large piece of metal. This would cool the metal quickly. A small area with a small flow (my maze2 3/8" lines) will cool as well as a large flow over the same area as it is restricted by the passages and the single line in and out. I.e. if the processors heat sink is only 1/2"x 1/2" then whether you poor a gallon or ten gallons on it is irrelevant. It will hit the temperature of the water and stabilize (max potential) with either volume at static heat load. I do not think this applies in pressurized high velocity cases.