I know it's a weird question, why would anyone not want to use the SP3 screen itself as a screen? I am hooking up my iMac 27 to my SP3 and would like the bigger screen real estate to do photo editing on when I'm at home. Is there a way to just have the screen blank out but still be able to use the surface to draw using the pen while only using the iMac as the source monitor? I know about the mirroring option on the SP3 but I would think it'll cause less lag when not utilizing the sp3 screen. If any of you have tried this method please let me know how well it works before I plop down $30 for a MDP to MDP official cable. Thanks!