Top Nurse said:So I am curious as to why you guys don't use push-fits? Seems you could really get some flow gains by actually having a true 1/2" ID. Also makes me realize that a 1/2" ID tube may only be seeing say 3/8" ID...so a 3/8" ID setup with push-fits may be a better way to go in that scenario?
The main reason is lack of space. 1/2" ID tubing pretty much implies 3/4" OD, and can you imagine trying to squeeze a 3/4" push-fitting onto most waterblocks? This is especially an issue with middle-in blocks. Where does one then locate the outlet fitting?
Maybe less of an issue with modern CPU's with widely spaced mounting posts, but with the older Socket A and Socket 370 (Pentium 3) mountings it was seriously an issue.
The scale of the issue isn't terribly serious though unless trying to achieve >10LPM flow rates at which point then the barb fitting transition resistance does start to become somewhat significant for many pumps. Still, even at this point, 3 transition points worth of resistance still only equates to about the same level of resistance as the 1/2" ID tubing itself is offering, so it's not a total flow killer.
One of the issues with push-fit fittings though is that they are (obviously) OD dependent, and this can limit the range of tubing choices. If we stuck 3/4" push-fittings on every-block, then people would be forced to use 3/4" OD tubing, and couldn't use anything smaller if they wanted to.
Finally, with more modern waterblock development, actual flow rates of >8LPM generally are totally unnecessary, unlike 3 years ago where >10LPM flow rates were desirable, nowadays that's more like a far more reasonable 6-8LPM actual flow rates that makes for a top-end performing high-flow setup, and at 6-8LPM, the barb transition resistance isn't heavily significant at all, especially in comparison to the waterblocks.