I completely agree.
My AIO is an H105. Perhaps I did better in the pump lottery than others, but I would be completely unhappy with its noise level if this AIO were fitted in, say the Air 540 case. The fans aren’t particularly quiet, either, so UEFI fan speed control, or a stand alone controller is absolutely mandatory.
You make a good point about using a good quality pump that operates at low RPMs. There is certainly a limit as to how much noise a good case can mask and the faster something spins, whether it is a fan, or a pump, the more noise it will produce. Another factor to consider is that while a case may mask the radiation of pump and hard disk noises, for example, that case may unfortunately do a particularly good job of transmitting these noises directly into surface upon which the case is resting. My Raven v2 case is particularly good example of this. If sitting on the carpet, it is completely silent, but if it is sitting on my credenza, the hard disk noise drives me absolutely crazy! The case feet are very rigid and provide no damping, whatsoever. I must set this PC on an insulating pad, in order to use this machine while it is setting on the credenza. So, the moral of the story is that even if the components are relatively quiet, you must pay particular attention as to how they are mounted to the case. And, just because the case has noise damping, that doesn’t mean that the manufacturer didn’t cut corners on the case feet, or some other important case component.
I probably should have mentioned that my D5 pump is the model with the variable speed potentiometer built in. IIRC, it has five speed notches in the pump body to indicate relative speed. These are high speed, high volume general purpose pumps and high speed, high volume simply is not required for PC water cooling purposes. The water needs to spend a finite amount of time in the water block in order to to absorb the heat and likewise, it needs to spend a finite amount of time in the radiator(s), in order to dissipate the heat. I have the D5’s potentiometer set to the second notch, which keeps the noise production down and still provides more than adequate flow. If this pump was running wide open, or if it was the model with no speed regulation, it would be intolerable in the Air 540 case. I’ve run it a maximum speed when bleeding the cooling loop and I can affirm that it is not only loud, but the noise is at a particularly annoying frequency.
So, I would suggest that noise management must be approached in the same holistic manner that PC performance is approached. You must consider all of the parts and how they will interact with each other as a whole. A quiet case will not tame an ill-conceived combination of parts, but it can make a borderline combination quite pleasant to use. It is also important to reflect on the fact that we all perceive noise differently and we all have differing expectations. Personally, I find hard disk noise to be among the most annoying and objectionable. Back in the day, when the TDP’s of CPUs and GPU’s began to creep across the triple digit threshold, it was not uncommon to have extremely loud case fans … and power supplies were among the worse offenders. Thankfully most of these designs have been relegated to the server room and today, modern PCs are/can be quieter than they ever have been. It probably won’t happen by accident, though. As with any build, thorough planning, a critical selection of parts and careful assembly is required, in order to achieve the desired results.
