Hello all,
I've been looking into water cooling a PC and I was wondering if anyone has used swage connectors. They use ferules & a retaining nut to securely connect to tubing. I build some water cooled instruments in a vacuum chamber which is one place that a leak is even more disasterous than on a motherboard. We quickly stopped using any barbed connections and used only swaged connections. You can find brass swaged fittings from McMaster Carr at a pretty reasonable price. They can be used with nylon (or metal) tubing.
Relative to a swage fitting, a barb has two major disadvantages. First, high pressure tends to push the tube of the barbed connector. A swage connection actually gets tighter at high pressures. The tubing will rupture before the connection fails ( I found this the hard way.) The second problem we found was that plastic tubes tend to flow over time, so connections started leaking after months or years. If you 'really clamp down' on the tube, it often gets worse! The plastic tubes will flow all the faster if you apply more pressure. I suspect that silicon tubes will hold up better than the Tygon tubes I used in the lab, but I would strongly recomend that you consider using swaged connections.
To find inexpensive fittings, see
http://www.mcmaster.com/ goto the Compression Tube Fittings (page 5 for inexpensive brass fittings)