I have 2 acer s271hl hdmi monitors, one suddenly started acting up, as in while powering on PC the screen displays everything fine until the login to the desktop comes up then screen goes black no signal appears light on power button goes to amber. I've connected a roku to this monitor to determine If it's my pc, again while roku powers on the screen displays the purple background displaying "ROKU" in the center, color and brightness etc is all perfect, once roku finishes starting up, again screen blacks out says no signal light turns amber. I've not got a device with vga , my pc vid cards have hdmi dviand some other connection but not vga so I can't try using that, I've got no dvi cable, but since the screen works fine I assume the monitors able to connect and read via hdmi, since does same thing on different devices I can only assume it's something with monitor. I've also tried unplugging hdmi and replugging back in, nothing happens to show the monitor detects or recognizes that as it doesn't do anything after taking hdmi cable off and back on. anyone have ANY ideas on what could be going on?