In today's workflow, it often happens that the main computer screen is overflowing with windows, and there are not enough options for expanding the workspace. Use a laptop as a second monitor for your PC via WiFi. — is the ideal solution for turning a portable device into a fully-fledged additional display without purchasing expensive hardware. This approach is especially relevant for freelancers, programmers, and traders who critically need to see multiple charts and windows simultaneously.
The main advantage of this method is that it eliminates the need to search for special cables or adapters, which are often lost or simply don't fit modern slim Ultrabooks. A wireless connection allows you to place a "second screen" anywhere in the room, ensuring maximum ergonomics for your workspace. However, it's important to keep in mind that image stability directly depends on the quality of your local network and the bandwidth of your router.
In this article, we'll take a detailed look at the software and hardware methods for achieving this goal, assess potential latency, and suggest optimal settings for a comfortable experience. You'll learn which applications provide minimal ping, which are best suited for static content, and how to configure your system for clear and responsive images.
Network and hardware requirements for stable operation
Before you begin software configuration, you need to make sure your infrastructure is ready to transmit video streams. Wireless video transmission It requires significant bandwidth, so using the WiFi 5 (802.11ac) or, ideally, WiFi 6 (802.11ax) standard is strongly recommended. Older routers that only operate in the 2.4 GHz band may not be able to handle the data flow, resulting in artifacts and lag.
Both devices—the main PC and the laptop/monitor—must be on the same subnet. This means they must be connected to the same router. Using guest networks or different access points (even with the same name) can block direct connections between the devices, as client isolation is often enabled by default.
⚠️ Important: If your router supports dual-band operation, make sure both devices are connected to the 5 GHz network. The 2.4 GHz band has low throughput and high noise levels, making using a second screen virtually impossible due to input lag.
It's also worth checking your Windows firewall settings. Built-in protection often blocks incoming connections required for screen streaming. Ensure that your firewall rules allow connections for the streaming apps you've selected.
Built-in Windows tools: Project to this PC
Windows 10 and 11 operating systems offer a native solution that doesn't require third-party software. The feature is called Projection onto this computer and is based on Miracast technology. This method is advantageous because it's already integrated into the system, but it can be less stable than specialized software.
To activate the receiver mode on the laptop that will act as a monitor, go to Settings → System → Project to this PCIf the items are inactive, click Additional components and install the "Wireless Display" component. After installation, in the settings section, select to allow connections from any devices on the same network.
On the main PC, press the key combination Win + KYour laptop should appear in the list of available devices that appears. Once selected, the connection process will begin. It's important to note that this method often results in a noticeable cursor lag, so it's best suited for displaying static information rather than dynamic work.
Why might the Miracast feature not work?
This feature may be unavailable if your WiFi adapter drivers don't support Wi-Fi Direct technology or if your graphics card isn't Microsoft-certified. In these cases, updating your drivers from the manufacturer's official website often resolves the issue.
Software solutions: Spacedesk and Splashtop
When built-in Windows tools fail to meet response speed requirements, specialized utilities come to the rescue. The leader in this niche is Spacedesk, which demonstrates excellent performance even on less-than-ideal networks. It operates on a client-server principle, with the driver installed on the PC and the client application on the laptop.
The second popular option is Splashtop Wired XDisplay (also has a WiFi mode), which is renowned for its low latency. These programs use proprietary compression codecs, allowing for faster image transfer than the standard Windows protocol. Installation is usually straightforward: simply download the distributions from the developers' official websites.
☑️ Installing Spacedesk
After installing and launching the apps on both devices, they should automatically find each other on the local network. You'll see the server's IP address in the client interface. Clicking it initiates a connection. If the connection fails, check to see if your antivirus software is blocking the app's network traffic.
Setting screen resolution and orientation
After successfully connecting the image, the new screen may default to a duplicate of the main one or have an inconvenient resolution. To configure it correctly, right-click on the desktop and select Screen parametersIn the window that opens, you will see a diagram with two monitors.
Select the second monitor (laptop) and scroll down to the "Scale and Layout" section. Here you can change the resolution to the native resolution of the laptop display, for example, 1920×1080 or 2560×1440. This menu also adjusts the refresh rate: for comfortable work, try to set it 60 Hz, if the network allows.
Don't forget to select the display mode. To expand your workspace, select Expand these screensThis will allow you to drag windows between the main monitor and the laptop. You can also adjust the orientation (landscape or portrait) and the relative position of the screens by dragging the rectangles with the mouse.
| Parameter | Recommended value | Impact on work |
|---|---|---|
| Permission | Native | Clarity of text and interface |
| Frequency (Hz) | 60 Hz | Smooth cursor movement |
| Color rendering | 32-bit (True Color) | Image quality |
| Scale | 100% - 125% | Size of interface elements |
Eliminate lag and optimize performance
Even with good hardware, lag can occur. The main cause is WiFi congestion. If you're using your laptop as a second monitor, try closing all heavy applications, torrents, and downloads on it to free up network resources for the video stream.
Quality options are often found in the settings of streaming programs (such as Spacedesk). If you experience lag, try lowering the Color Depth setting or selecting "Speed" instead of "Quality." This will reduce the amount of data transferred and improve FPS.
⚠️ Note: Program interfaces and available codecs may change with updates. Always check the current settings in the "Help" section or on the developer's website if the default settings don't work.
Another effective method is to use a wired connection for one of the devices, if possible. For example, if the PC is connected to the router via a LAN cable and the laptop is connected via 5 GHz WiFi, stability will be significantly higher than connecting the two devices exclusively via wireless.
Comparing Connection Methods: WiFi vs. Cable
Although this article focuses on wireless connectivity, it's impossible not to mention the alternative. A wired connection (HDMI via a capture card or Ethernet) will always be superior in terms of stability. However, when portability and the absence of unnecessary cables are paramount, WiFi remains the undisputed winner.
Using WiFi gives you the advantage of aesthetics and placement flexibility. You can place your laptop on the couch, move it closer, or move it away in seconds. A cable system requires a permanent location and available ports.
On the other hand, a second monitor via WiFi may be unsuitable for video editing or gaming due to compression artifacts. For office tasks, coding, reading documentation, and chatting, this method is ideal.
Frequently Asked Questions (FAQ)
Is it possible to use a laptop as a monitor via WiFi without installing programs?
Yes, using the built-in Windows "Project to This PC" feature. However, its stability and connection quality are often inferior to specialized utilities like Spacedesk.
Why doesn't the laptop see the computer on the local network?
Most often, the problem lies in your network settings. Make sure the network profile is set to "Private" and not "Public," and that both devices are on the same subnet (the first three digits of the IP address are the same).
Does using a second monitor affect FPS in games on my primary PC?
Yes, encoding a video stream for a second screen puts a strain on the processor and graphics card. In demanding games, this can result in a 5-15% performance drop.
Which router is best for this task?
The optimal choice would be any modern router that supports the WiFi 5 (AC) or WiFi 6 (AX) standard and has a separate 5 GHz band.