hello,
sorry for just jumpin in. haven't read the whole thread, and i don't know all details, i just want to say:
my current (ya)vdr: - asus at3iont-t (deluxe, for extern 19V) attached to my flat, sound over hdmi - it has serial port, and one pci-e. - mc-1200 case (but built-in remote not really working yet)
the only noise is now coming from my harddrives, as this machine currently is more than a video player. so an ssd would make this machine completly silent. sometimes the cpu heat is nearly 60C°, but as i said, i do more than just watching tv and hd movies. in this case, the machine gets instable.
xbmc can play 1080p, but more details i can't say, for i have not that knowledge...