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Going from out to out port is it possible? do you have to follow the labels?

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Oct 7, 2016
So I am building my first loop and I have a question that I cant seem to find any information anywhere about. What I want to do is run my water hose from my pump labeled (out port) to my cpu block labeled (out port) is this possible or do I have to follow the labels in to out and out to in? do the labels matter? any information would be greatly appreciated thankyou
The in and out of the pump ports must be followed obviously because the pump is only designed to work in one direction.

As for the cpu block, the waterblocks are designed to have water flow in a specific direction for better efficiency. If you reverse the flow of water through the block it will still work in most cases but you will not get great heat transfer from the block in this manner.
Thanks for the quick reply Lochkey guess that makes sense but my gpu block and radiator have no labels why dont certain components have no labels?
If there are no labels they are designed to be bidirectional instead of unidirectional.
ahhhhh ok so I will re plan my loop order I suppose Thanks guys
Your welcome feel free to post up some other questions if you run into problems were are here to help.

We always love to see people's builds so you should post up some pictures as you go along.
sounds good I will no doubt be asking more questions as I go along and also I plan on not only posting some pics but some video as well
I had my CPU block piped in reverse and it made around 10 degC difference..... If a block has an "IN" and an "OUT" label, then they are designed to have water flowing a certain way with minimal cavitation etc so a revers flow can affect that. People will say that the loop stabilises temps etc, but the actual exchange of heat from block to water is where the business takes place, so make sure you get that right!