Bill@ASUS wrote:
Hello Koutport
Do you have another monitor to test this with? We can rule out the monitor easily if you have one.
Maybe this is due to the the graphic card or Windows settings.

Koutport wrote:
Hello,
I have another monitor but there isn't any problem with it.The different between the 2 monitors is the connection.With the DVI port everything its OK.The PG278QR has only HDMI or Display port.The monitor is new (about 1 month).
The graphic card(980 MATRIX) has 2 display port and 2 HDMI port, I try all the ports but the problem remain.
Consider that the problem appears only as soon as playing games , on WINDOWS or surf on Internet everything its OK.
Thanx

Bill@ASUS wrote:
Hello Koutport
Do you have another monitor to test this with? We can rule out the monitor easily if you have one.
Maybe this is due to the the graphic card or Windows settings.

Korth wrote:
Check end connections on your DisplayPort cable. They can appear properly plugged in while only partially inserted. Chassis dimensions might interfere with proper GPU-side physical connection.

Check that your PCIe GPU card is firmly seated. Check that the 6-/8-pin PCIE12V power connectors are firmly connected, swap/replace power connectors if you have spares.

Test the monitor with a different DP cable, if you have one. Test monitor on different computer and/or different monitor on computer, if possible.

Check all PCIe, GPU, and power saving or "screensaving" options in Windows control panel, NVIDIA control panel, BIOS, and the monitor OSD.

Are your GPU temps spiking or fps stuttering just before signal loss? It could be a thermal failure.