@SirNick
I have considered the option to just make a low noise computer, but it is my last choice at the moment.
I think I will buy a couple of decent HDMI cables to test if it works - if it turns out great, I will do the same stunt with the HTPC in the living room.
@gxti
Well, I'm not using usb that much - only for keyboard, mouse, jtag and other programmers, so the speed is not that big an issue, so USB2 might be the best solution from a price point of view. But of course if the price is right, USB3 is more future-proof.
Thank you all for your comments! I will do some tests, and get back with my results.
BR Jonas