Hi
@IcyStorm
To your first question.
Which thickness you should choose depends a bit on how you want to build your own system. If you only want to install fans on one side then the 30mm thick is the perfect choice, if you want to install the fans on both sides then the 45mm thick is the better option. For even thicker ones like the 60 or 86mm thick radiator, the fans have to be mounted on both sides and they have to rotate correspondingly faster (1500rpm and more) to get better cooling performance.
How much heat a radiator can dissipate cannot be said directly because there are too many things to consider. Especially on the installation situation and the fans used. If the radiator has enough access to fresh air or exhaust air (housing with mesh grid), that's better, it would be worse if the housing has glass installed here or is isolated by additional mats for dust and noise that can hinder the necessary airflow.
And from the fans themselves, at what speed do they run (some are better than others at low speeds), what static pressure can they reach (more is better), and above all are these fans suitable for radiators. But all in all you can say that a 120mm radiator can dissipate a good 100 watts at low speed (silent operation), a 140mm creates around 130 watts. And if the fans are allowed or able to turn faster, the delivery volume will of course also be higher. As an example, a 360 with 30mm can dissipate a good 1500 watts without any problems, but the fans have to run at 4000 rpm.
To the second question:
In order for the 45mm to have an advantage over the 30mm, fans must be mounted on both sides of the 45mm with the same fan speed or, with one-sided assembly, they must rotate faster (1000 rpm and more).
Bedt Regards