Display modes determine how your computer handles the various displays connected to it. This includes monitors, projectors, etc...
There are four basic display modes.
PC screen only
Video will only show on the main screen. The name is somewhat misleading as this could be your monitor or your projector. This is the screen where all desktop icons are displayed by default.
Both displays will show the same image. This should be the most familiar mode of operation. Depending on size variances between displays this mode may cause letter boxing.
Displays are treated as separate and display different things. This is similar to a dual-monitor setup.
Second screen only
Video will only show on the secondary screen. The name is somewhat misleading as this could be your monitor or your projector. This is the screen where all desktop icons are displayed by default.
In most cases, only duplicate or extend modes will be used. In some cases the computer may default to one of the other modes so it is important to be familiar with them.
Troubleshooting Display Issues
Monitor is black but the computer is on (or vice versa).
If the cables are firmly seated between the display and the computer, the computer is probably in PC screen only or Second screen only mode.
- Turn on the projector. (This should allow you to see what is happening)
- Use Windows Logo + P on the keyboard to cycle through display modes to select either Duplicate or Extend.