I think I am going to buy a Display Port cable because of the higher bandwith so the higher framerate it can support. But I heard that Display Port is unable to proces as many colours.
Can someone clear this a little bit up for me?
At higher than 1440p, the Displayport needs to be daisychained to get maximum colors. The downside is it doesn't sample in audio like the HDMI does. If you're running 1080p it doesn't matter at this point, stick with the HDMI for less wires. Good luck!!
If you don't have a requirement for audio, then I recommend DisplayPort.
It partially depends on your Monitor. Many of the HDMI inputs on monitor are there for DVD/Bluray/console support and work the same as an HDTV does. If so, you then need to properly setup 1080p_NTSC@60Hz etc. In addition, you are locked into that resolution and can't change it in a game.
I don't have enough information to know if that's common or not though.
You mention "higher bandwidth" so you really need to consult your manual for the Monitor to see what is supported using the various inputs.
My monitors is 2560x1440 but that's by Dual-Link DVI or DisplayPort. It does NOT support that resolution with HDMI.
I've never heard of a scenario where HDMI was "better" than Displayport but I could be wrong.