high restriction vs low restriction??

[orthomofo]

can someone please help me understand the significance of high restriction vs low? and how this will impact my wc setup. i haven't really taken that into account while planning my sys because I don't know how to.

my sys will evolve over the next year as i add more GPUs

1st - in no particular order
start with
CPU -- 1 GPU -- NB -- rad under water

then...

GPU -- NB -- rad on one loop
&
GPU x 3 -- rad on a separate loop

after advice on my pump i was thinking of using the D5 and eventually have 2 of them when i split the loops

the new cpu block from swiftech is on my menu for a CPU block

[QuietIce]

High restriction is just a matter of what blocks you use and how many in a given loop. Most blocks today are low restriction unless they're full coverage GPU blocks or require 1/4" tubing like some chipset blocks - and even then it's really minimal impact unless there are several of them.

In any event the D5/MCP-655 (and the MCP-355 as well) will push right through almost anything you want to throw at it ... :)

[voigts]

Restriction of course refers to the resistance components, tubing, fittings, etc. give towards water flow. There is a balancing act in blocks where higher restriction tends to allow for better cooling due to waterblock design, but too high of a restriction hurts flow too much. You want to use a decent sized tubing of at least 3/8" ID, and minimize using sharp 90 degree fittings and such. Tubing smaller than that and especially the sharp plastic elbows offer too much unnecessary restriction that can hurt your flow rate. It is better to use copper elbows or Bitspower elbows or such that have a nice curved transition if you have to use elbows as they offer a lot less restriction to flow.

I would recommend you take a look at Martin's flowrate estimator (from over on xtremesystems) at http://www.martinsliquidlab.com/MartinsFlowRateEstimator.html. This wonderful tool can give you an idea of what components put together will give you what result.

The Apogee GTZ is so new that very little testing has been accomplished on it yet. First testing however indicates that it is a very good block as far as performance and restriction goes. The hold down mechanism looks the best of any block on the market.

[orthomofo]

thanks guys:beer: