I use a Fortron FSP-350 power supply.
It's 350W have been supplying my system with quite a lot of drives connected, reliably for some time now.

As I wanted the water-cool-system to switch on when pressing the "On" button on my case and off again when selecting "Shutdown" from Windows, I had to have the power supply control  the water-pump.
I also didn't want to have anothe 220V cable coming out of the back of my case (the water-pump is 220V).

In order to achive my goal, I opened up the power supply and soldered the 220V leads of the water-cooler to the 220V leads of the power supply.
To do this I had to completely take apart the power supply as can be seen in the picture above.

Now all I had to do was think of a way to switch the water-pump on and off as described above.
The solution was fairly simple, I inserted a 12V relais (220V switching) in one of the 220V leads of the water-pump.
The 12V-side of the relais I connected to one of the 12V supplies coming from the power-supply (see picture above).

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