This guide explains how a PC can switch a monitor's input at all, how to set up the keys step by step, how to plan your way back to this PC, and what to check when a key does not switch.
Who this is for
- You share one monitor between this PC and a laptop, for example a work laptop on USB-C and your desktop on DisplayPort.
- A console shares your screen: the console on HDMI, the PC on DisplayPort.
- You switch inputs several times a day and are tired of finding the input menu with the monitor's own buttons.
With a key for each input, switching becomes a press on the Stream Deck. The key also shows the monitor's current input when the monitor reports it, and lights a green border when the monitor is on that key's input.
How a PC can switch a monitor's input: DDC/CI
Your video cable carries more than the picture. Alongside it runs a small control channel called DDC/CI (Display Data Channel Command Interface). Through it, a computer can read and change settings that you would otherwise change in the monitor's on-screen menu. Each setting has a number, called a VCP code. The input source is VCP code 0x60.
Monitor Input Keys for Windows writes only that one setting. It does not touch brightness, color or any other monitor setting. Three things follow from how DDC/CI works:
- No extra hardware. It uses the HDMI, DisplayPort or USB-C cable you already have.
- DDC/CI has to be on. Most desktop monitors have it, but some ship with it turned off. Turn it on in the monitor's own on-screen menu, sometimes under "Other", "System" or "Setup".
- The channel has to reach the monitor. A direct cable from the PC to the monitor is the simplest path. The checks further down cover docks and adapters.
Before you start: plan how you will come back
When the monitor switches to another input, it shows the other computer or device. What happens on this PC's side depends on the connection:
| Connection to this PC | After you switch away | How to come back |
|---|---|---|
| HDMI | Many monitors stay visible to this PC | A second key on this Stream Deck switches back |
| DisplayPort, USB-C | The monitor usually disconnects from this PC | From the other computer (for example with this plugin on a Stream Deck there) or with the monitor's own buttons |
This is also why a key asks for two presses by default: a stray press does not send your screen away. You can change it to one press per key once you are used to it.
Step by step: set up a Switch Input key
- Install Monitor Input Keys for Windows from the Elgato Marketplace. It runs on Windows 10 or later with the Stream Deck app 6.9 or later.
- In the Stream Deck app, find Monitor Input Keys for Windows in the action list and drag Switch Input onto a key.
- Select the key. Under Monitor, choose the monitor. The list shows the monitors connected now, and the button next to it looks again. With only one monitor you can leave it empty.
- Under Switch to, choose DisplayPort 1 or 2, HDMI 1 or 2, USB-C, DVI or VGA.
- Press the key. The first press only shows where the monitor will go: an amber frame and
PRESS AGAIN. Press again within 3 seconds to switch. To switch on the first press, set Press to Once. - Make one key for each input you use. With several monitors, each key picks its own monitor from the list.
One key for all inputs: Cycle Inputs
Drag Cycle Inputs onto a key, choose the monitor and tick at least two inputs, including the one this PC is connected to. The key shows the input it goes to next. Press twice, as above, to switch. Until two inputs are ticked, the key shows choose inputs and does not switch.
What the key tells you
| The key shows | Meaning |
|---|---|
now DP 1 | The monitor's current input. now ? means the monitor did not report it; some monitors can switch but not report the input. |
Green frame, active | The monitor is on the input this key switches to. |
Amber frame, PRESS AGAIN | Press again within 3 seconds to switch. Nothing has been sent yet. |
Green, SWITCHED | The monitor reports the new input. |
Green, SENT / monitor left PC | The switch was sent and the monitor then left Windows: it is showing the other input now. |
ALREADY | The monitor was on that input already; nothing was sent. |
If a key does not switch the monitor
NO DDC/CI: the monitor did not answer DDC/CI. Turn on DDC/CI in the monitor's own menu. Laptop screens do not support DDC/CI, and many docks, adapters, KVM switches and DisplayLink connections do not pass it on, so connect the monitor directly to test. The Status line in the key's settings gives the Windows error code.NO MONITORornot connected: the chosen monitor is not connected to this PC now, or it is on another input (see "plan how you will come back").NO ANSWER: the monitor did not answer in time. Try again; if it keeps happening, connect the monitor directly rather than through a dock.- Gray
SENT: the switch was sent, but the monitor still reports another input, or nothing. Some monitors ignore an input with nothing connected to it, so check that the other device is plugged in to that input. - Your monitor uses other input numbers: some makers use their own values (for example some LG models). Choose Other and enter the input code, such as
0x11or17. The Status line lists the values the monitor itself reports. - The monitor is on a duplicated display: a monitor under "Duplicate these displays" is not switched, because Windows does not say which physical monitor is which. Use "Extend".
helper error: the plugin's helper, Windows PowerShell, could not start. The Status line gives the reason. On a company PC a policy may block it; ask your administrator.
Frequently asked questions
How do I switch my monitor from HDMI to DisplayPort with a Stream Deck?
Add a Switch Input key from Monitor Input Keys for Windows, choose the monitor and set Switch to DisplayPort 1 (or the port you use). Press the key, then press again within 3 seconds, and the monitor changes input. Make one key for each input you use, or one Cycle Inputs key that steps through them.
Do I need extra hardware or a special cable?
No. It uses DDC/CI, the control channel in your normal video cable. If DDC/CI is off, turn it on in the monitor's own on-screen menu (sometimes under Other, System or Setup).
Can I switch back to this PC from the Stream Deck?
Yes, while this PC can still see the monitor. Over HDMI many monitors stay visible, so a second key switches back. Over DisplayPort and USB-C the monitor usually disconnects from this PC, so switch back from the other device or with the monitor's buttons.
Can it control more than one monitor?
Yes. Each key switches one monitor, which you choose from a list in the key's settings.
Does it change any other monitor setting?
No. It writes only the input setting (VCP code 0x60). It runs entirely on your PC, with no account and no online service.
Related
- Monitor Input Keys for Windows: what it does, how it works and its limits
- Monitor Input Keys for Windows support page
- How to Black Out a Second Monitor from a Stream Deck (Plus a Sleep Timer)
- How to Show CPU, RAM, Disk and Network Usage on Stream Deck Keys (Windows)
- All GRAMSHIFT Stream Deck plugins for Windows
- All GRAMSHIFT guides
- Stream Deck でモニターの入力（HDMI・DisplayPort・USB-C）を切り替える方法