New RiMac 27". I am attempting to set up a dual display. The second display is a 32" BenQ cad monitor. It's WQHD 2560 x1440 resolution. The BenQ monitor has Displayport input as well as DVI, HDMI, and D-sub. I ran a mdp to dp cable to the monitor. I have black screen on the BenQ monitor. This is the same cable I use successfully with this monitor on my 2010 mbp. I have also noticed with the BenQ monitor attached, my magic mouse became jumpy and very difficult to control. ETA: Hooked it back up to the MBP. Took a couple tries to get it working - but it's fine on the MBP. ETA 2: Hooked it back up to RiMac. Turned on mirroring, which sets display as best for the BenQ monitor. The RiMac is detecting the second monitor. The BenQ monitor remains black and flashes the no signal detected warning. I've tried reducing the resolution from WQHD to 1080i to 720 - no change in the BenQ monitor.