First of all, sorry for replying so late.
I have identified the problem already, which was my stupidity at its highest :P
4 pin and molex adapter for the H80 MUST be plugged in at the same time, one for controlling the fans and one for its power, my CPU is at 29 degrees now. What I did was have the 4 pin plugged in and the molex left aside, because I was afraid this would overpower the pump and fans ... I mean, it made sense from my point of view back then ... but I was really wrong. (By the way, they do not mention this on the instruction, so I was confused)
Everything seems perfect now, I also bought and installed 8GB Corsair Vengenance RAM, I have not encountered a single problem since then.
Thank you for your help, once again, this forum has solved my problems and my computer is running like a dream.