Bought myself a new gigabyte switch. Didn't realize that all my stuff supported the higher speed, and the old switch was holding them back. Also some bad cables. You really need the higher speed for the hd movies.
I also had to improve my zotac. I was running xbmcbuntu which was at an old version. I put on the latest Debian kernel, which had all the latest drivers for the ethernet and the Intel graphics chip, and something extra for the duo Atom chips. The picture is much better, and there is no more hesitation on the extremely busy scenes (try Hello Dolly!). I did run into the infamous tmpfs problem, and this can be solved by various means. I did two things at once "make localmodconfig" and a change under 'Generic drivers' for the tmpfs. So I don't know what did it.
This zotac only does 720p which is enough for a 50" plasma in a small room. The resolution is amazing. If you have a bigger screen, and you like to sit with your nose touching, then you need the latest zotac. :) I simply can't imagine a 4K screen! The high resolution is distracting for a first view, it is only good after you've watched your Jane Austen a dozen times! (Look at that lace!)