

I tried detecting it thru the windows display properties.that didn't work.

I finally got it to work except I don't know exactly what I did. I tried lots of things.(my displayport cables are only about a week old, as I recently replaced my older ones with new "approved" ones).Unplugged and plugged back in the display port cable from both the problem monitor and video card, unplugged and plugged back in the power cord to the monitor, exchanged displayport cables with a monitor that was working, turned the monitor on and off several times, shut down the computer and turned it back on.funny thing, when I shut down the computer and turned it back on, I thought that fixed it at first, because when Windows was starting up, both monitors showed the "Windows is starting" message with the animated logo showing, but instead of showing the desktop, the problem monitor just went black with the "no display port" signal. Turned my monitors off while I left the room for awhile, then when I got back to the computer, turned 2 monitors on, but one of them had the "no display port" signal. I have 4 pb278q monitors connected to a AMD firepro V7900 card.had this setup for over a year. I'm hoping that's the solution for whenever this happens, because beyond this nuisance bug, I'm very happy with the monitor. And then I remebered how it worked after I had tried the VGA, and doing that again (temporarily displaying through VGA) restored the DisplayPort capability. No sequence of rebooting, switching input modes, messing with the NVIDIA settings or re-plugging of the DisplayPort cable would bring it back. But then it hit again, and I think what happened was that the desktop power management feature put it to sleep. And then it worked without issue for a few days through reboots of the laptop and power cyclings of the monitor. But then when I tried DisplayPort again it worked perfectly (full 2560x1440). Initially when I first tried it out, I couldn't get it to receive a DisplayPort signal at all, so then I tried the VGA cable, and VGA worked (at 1920x1080). It sounds like in some cases it doesn't know when to awaken after it is put to sleep. From reading this and other threads, it seems to be an issue with the PB278 monitor. I recently bought this monitor and had the trouble with no DisplayPort signal.
