Ok, so i've reinstalled the video drivers
and the flickering of the screen (in vga and dvi) and the often no video input on the dvi connection still happens... So i've hooked up my old LCD on, with his VGA connection, and it doesn't flicker at all. So the monitor itself could be broken. Is that posssible ?
+ the LED Philips 222EL2SB 21.5 inch 5 ms wide black,on the DVI connection, doesn't even want to show the bios image + the loading of it, until it reaches the windows user password window (log-in screen). While on the same monitor,on VGA, it shows the image right from the beginning with the motherboard image and the bios loading etc.