That monitor has only a DVI cable. I am using a new Apple-brand Mini DisplayPort to DVI adapter. When I unplug the adapter, my Mac's screen flashes as if it noticed a monitor was detached. But at no point does the external display show anything. The monitor's power light is on. The USB pass-through works for the keyboard. I've tried both of the MacBook Pro's Mini DisplayPort ports.
Tried the old reliable ⌥+⌘+P+R to hear the startup bong noise three times. No go.
The monitor works when plugging the same Mini DisplayPort adapter into a MacBook Air the older OS, 10.8.5.
Confusingly, my new MacBook Pro works well with another Apple monitor, the 24-inch Cinema display with built-in Mini DisplayPort cable and LED backlighting.
So the problem lies with either:
- the MacBook's hardware, or
…failing to handle a DVI monitor (even an Apple-branded DVI monitor).