I have a NEC 302 W 30 inch monitor (about 8 years old) connected via display port to my 2013 MacPro (OS 10.14.6). I use a wired mouse and keyboard, both connected by a USB cable. PS and LR are on the boot drive, my photos on an external spinning drive connected by USB. Occasionally while working on photos my screen goes black for about a second and then returns to normal. Any thoughts about what could be causing this? I just replaced my mouse and the problem keeps happening.
