The big radiator material test: Between promise, reality and the forbidden – Water Cooling tested more in Detail! | Part 1

1 - Intro, Samples and Equipment 2 - Alphacool NexXxoS ST30 Full Copper X-Flow 120mm 3 - Aqua Computer airplex radical 2/120, Alu-Lamellen 4 - Bykski CR-RD120RC-TN-V2, D30 V2 Full Copper 5 - EKWB Quantum Surface P120M - Black 6 - Hardware Labs Black Ice Nemesis GTS - 120 XFlow 7 - Watercool HEATKILLER RAD 120-S Black 8 - Summary and Conclusion

Watercool HEATKILLER RAD 120-S Black

The last letter for today is a W. The Watercool HEATKILLER RAD 120-S Black closes the circle today and I ask for your attention one last time!

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As usual, let’s let the manufacturer himself have his say and they talk about channels and fins made of copper. Of course I’m curious about the “best raw materials”… Incidentally, the whole thing was still exactly the same on the homepage until yesterday, of course I took screenshots. The link leads to the waybackmachine, for good reason, as we’ll see in a moment:

The text was secretly adapted today after the article was published, but I have not yet received a statement from Watercool. In my opinion, clean marketing looks a little different. This is how the text reads now:

Unfortunately, Watercool’s marketing and reality don’t match up either and the way in which texts are secretly and quietly removed from the website is just as shabby as the false declaration. Instead of the advertised copper, we find normal brass with only average thermal conductivity in the ducts. This puts Watercool in the best of company, except that I’m not even sure that they know what they’re getting from China. I would step on the toes of my OEM very quickly and emphatically. The Bykski system, where you believe what is rubbed in your face as a PDF. Testing it yourself would probably have been cleverer.

And the rest of the test? After the table, which already anticipates and summarizes a lot, we now come to the test results for the last time, including pictures and further details.

Pre-chamber / terminal and solder

We see a fairly high soldering quality here with a dimensionally accurate use of solder. However, I would prefer to see an all-round layer of solder on the end faces of the channels and not such steps, because with a bit of bad luck this will result in weak points that cannot be seen from the outside. However, the smooth surface shows that it doesn’t always have to be so grey and dull oxidized even without lead and an extremely large amount of flux.

The solder as such is fine so far and the layer here is also relatively thin, so I got some copper as well. There is no lead, thank you.

The carrier plate of the cooling fins consists of around 72% copper and 28% zinc, which is fine.

The outside of this chamber, i.e. what the customer can see and touch, is made of, we guessed it, coated brass. We find CuZn35, i.e. 65% copper with 35% zinc. The pre-chamber is therefore made of this rather hard brass…

Let’s move on to the soldered threaded inserts, which are made of CuZn42 brass, i.e. 58% copper and 42% brass.

Cooling channels and fins

The most important part in the middle are the cooling channels and the fins, both of which the manufacturer specifies as pure copper. Let’s first take a look at the cut as such. The channel carries the slightly slotted fins, which are arranged quite closely together.

Let’s look at the measurement of the cut channel and yes, it is again exactly the 65% copper and 35% zinc content, i.e. brass CuZn35. This is significantly worse for heat exchange than pure copper and it is surprising why copper is used here. After all, it is not copper.

It looks better with the cooling fins, which only show copper. That was also the only thing that was really stated correctly.

Housing and accessories

Finally, we come to the side panels, the visually high-quality front panels and the enclosed screws. Let’s start with the frame. Hidden under the black powder coating is simple, stainless steel without additives, i.e. no stainless steel.

The brushed and chrome-nickel steel (iron 59%, chrome 29%, nickel 12%) on the end faces is of a much higher quality.

Which brings us to the screws for the last time (for today)…

… which are made of nickel-plated chrome-nickel steel, the composition of which is very similar to that of the end faces.

Interim conclusion

Watercool really didn’t need to specify copper on the radiator where there is none. I assume that the OEM has simply cut corners here and hopes that nobody will find it. It’s a shame, because you could have seen it with the naked eye from the color, you don’t even need six-digit equipment. A tip for Watercool: confront the OEM. That usually helps (at least for a while).