MacBook Pro Retina, questions about 2nd monitor for gaming

cpudisplaymacbook pro

I have a MacBook Pro Retina, and I'm gaming a lot with bootcamp windows 8. I'm considering buying a external monitor for better gaming (might be a BenQ, has to be 120Hz). My questions:

  1. Does a 2nd monitor affect CPU performance?
  2. If I buy a good monitor, is there only the latency from the monitor, or is there also other latency? (Some monitors have latency of 1ms, 5ms, which is quite good, and not a problem, but if there's more latency because it isn't my primary screen or something, I need to reconsider).

Thank you

EDIT:
And, I've also heard people say that it's useless to connect a 120Hz monitor to a MacBook because the videocard is only able to handle 60Hz. Any confirmation? (Hopefully not)

Best Answer

The GPU on your MacBook Pro will be driving two displays, which is a lot of pixels — gaming performance will definitely be affected by the addition of the second display. You'll probably have to drop the resolution of your games to get an adequate framerate.

As for the latency question, a wired second display won't have additional latency just because it's a second display.