It can be a bad monitor, no output on the PC or settings. I find folk struggle with settings because there are a dozen settings and a dozen different ways in the PCs I've run into. This means I can't tell you exactly how to setup your Acer laptop.
The laptop model eludes me so I can't see if Acer tells how either.
What's next? Try this monitor on a good PC to see if it works. If the display works on another PC or other source then we get back to the laptop's manual and the web.
It's frustrating and best done with a service call but we'll try here.
Not sure if this is the right place to ask but I couldn't find a monitor forum category.
Whenever I power up my acer laptop, the monitor doesn't seem to connect and instead says "input not supported". I've also tried booting my computer into safe mode however then my monitor says "no signal" in safe mode.
This has been happenening for the past couple days and I'm started to really get frustrated (as you can tell from my username).