You should be able to run both perfectly well. However I must say in advance that DayZ is still an alpha, meaning that a whole bunch of code wont have been optimized and will be full of bugs which could make it run laggier than what a final product will. Turning some settings down should fix that. The same goes for the mod version of DayZ, it's a mod so isn't optimized as much. Although, DayZ is an overall beautiful game, and I recommend it for the price it's at.