Need to upgrade server, need some advice please

I've got a 2700k, 16gb ddr3 and Asus P8Z68-pro

I'm looking to upgrade the system, I use it to monitor 4 1080p CCTV cameras and also as a media center to play HD Video.

Is there better alternative, what kind of cpu and motherboard is recommended and how much improvement will it be.

Performance wise I wouldn't have expected that to be even stretching its legs.