Yes, the computer is powerful enough to span between the internal display and the Dell at full res, although depending on how many windows you have open and what you run, it is possible that in some circumstances, you will get frame drops and/or stuttering. For productivity, you should have no problem whatsoever. For everything else, it will only be if you do a lot of tasks that use video card memory, have a lot of windows open, etc, etc. Should not be an issue.