AIO as a monitor

[aschumm]

can I use an AIO as a monitor for another PC

 

[USAFRet]

can I use an AIO as a monitor for another PC

Unless it specifically has an HDMI IN port, no.
And it is very unlikely to have that.

Look in your user manual to discover if that is the case.

 

[Solandri]

If there's no video in port, you can still use the AIO as a remote desktop client. Run Microsoft Remote Desktop Server on the PC, or a VNC server (I like tight VNC) on the PC (you'll need a real monitor or a TV for this initial setup). Then boot the AIO normally and run the appropriate client. Connect to the PC over the network via the remote desktop client. This will work for web browsing and office tasks. Not so well for video. If video or gaming is your thing, then probably something like Splashtop or Steam In-Home Streaming (if it can be configured to show a desktop) might work better. Those convert the PC's display into a h.264 video stream. Your AIO would just be displaying a streamed video of the other PC's display.

One of the early AIOs I took apart had an internal DVI port connecting the mainboard to the monitor's input, so in theory you could've plugged an external DVI cable into that. I believe all the newer AIOs have switched to laptop-style connectors now (LDVS / eDP). You might be able to get an adapter to go from a regular external video port to one of these (eDP is just Displayport), and hack the casing to give yourself an external video-in port.

But this is the reason I try to steer people away from AIOs. Unless you plan to use it for 10+ years, you are usually better off buying a separate monitor. Use that one monitor with the different desktops or laptops you buy over the years.