Top critical review
Not a bad monitor but a few issues.
Reviewed in the United States on November 10, 2016
Decent monitor but does have some issues. I have two of these and two of P2715Q as well. I work with DsiplayPort echnology so have some insights that may be helpful.
First, a word about DisplayPort cables. There are many in the market that do not follow the DisplayPort Standard because they carry the DP_PWR signal, which is provided at the connector to power adapters. If you can turn on your PC and Monitor and then connect the cable and it works, but cannot get one or the other to wake from sleep or power back on, you may have a bad cable. You can tell by unplugging the DP cable see that the device will wake or power on.
The monitor itself operates in three modes. Use the on-screen display (OSD) menu to navigate to Display. In those settings there is an option for MST (DisplayPort Multisream technology). MST is the feature that allows you connect these monitors in daisy-chain.
If MST mode Off, the monitor operates as 4k, 60Hz refresh.
In MST Mode Primary, the MST feature is turned on and the monitor operates at 4K 30 Hz refresh. That's because at 4k 60Hz, it uses up all of the DisplayPort bandwidth so a device connected to the DP Out port would not work.
In MST Mode Secondary, the monitor disables MST, declares itself to be "DP 1.1" and sets its resolution to 4k 30Hz. This is "compatible mode" and is default (out of box).
By the way, most Apple laptops do not support MST.
Regarding sleep/wake issues, this can be caused by an issue with monitor firmware. In MST mode, I've observed that the Hot Plug Detect (HPD) signal that the source (computer) uses to detect the monitor is connected is not always sent correctly by the monitor. It doesn't fail all the time and does not seem to affect MST Off or Secondary modes. I do a lot of sleep/wake testing with various sources and I only see failure to wake occasionally but often in MST mode with another monitor attached downstream.
I've spoken with the company that makes the DP chip and they fixed the issue but firmware updates for monitors in the field are not available.
If you aren't using MST mode, turn it off. If you think the image quality is not up to par, check to see if using Secondary mode and try MST Off instead.