Therefore urgently needed a new radiator. Because of my rather compact housing a 12cm fan found no place. Since I have chosen because of the good reviews on Amazon for the TX3 EVO from Cooler Master.
The installation was absolutely no problem even for a layman like me (thanks youtube and co). The radiator and the enclosed parts make a high-quality impression and the thermal grease is enough for several applications. Meanwhile, my processor is stable below 3 GHz (with slightly elevated voltage) and the TX3 EVO keeps it constant even after 2h 100% load at max. 61 degrees. In idle state, the nuclei around the 35 degrees warm. Compared with the boxed cooler, the noise is absolutely top. The cooler is very quiet even under maximum load and if the graphics card is running, this drowned out the TX3 EVO anyway far.
All in all a cheap cooler which provides an amazing performance for its dimensions. Even for overclocking it is, to some extent, are suitable. Has managed my high expectations even surpass yet.