My housemate and I regularly play games together using a Steam Deck and a large game library, but we're running out of local multiplayer titles that support two players on one system. We both have capable gaming PCs and don't mind buying separate copies of games. Ideally, we'd like to move one or both PCs into the lounge—or use two Steam Decks—and display each player's game on a different part of the same TV or monitor.
Most newer TVs don't seem to support combining two HDMI or DisplayPort sources into a split-screen view. Is there a TV feature, external device, or software solution that can merge two independent gaming inputs onto one display? Low latency is important, and advice about handling separate audio and controller inputs would also be helpful.
3 Answers
Some Samsung and LG televisions still offer split-screen or multi-view features, although the exact input combinations and supported resolutions vary by model. If your TV doesn’t support it, look for an HDMI multiviewer rather than a normal splitter—a splitter duplicates one signal, while a multiviewer combines multiple independent sources. Good units often cost over $200, especially if you need low latency and 4K support.
An HDMI multiviewer is probably the most direct hardware solution. It combines two or more video inputs into one output and can usually show them side by side or in separate quadrants. Many models accept four 1080p sources and output them as a single 4K signal, since four 1080p images fit within a 4K frame. Be careful with inexpensive units, though, because they may add noticeable input latency. Audio can also be awkward if both sources are mixed together, so using headphones connected to each gaming device may be simplest.
Software may be another route. Nucleus Co-op can launch multiple instances of certain games on one PC and add split-screen support where the game doesn’t provide it natively, though compatibility and controller assignment can take some experimenting. Alternatively, Sunshine on each PC with Moonlight on a Steam Deck or streaming box can get the games onto the TV, but that normally means separate streams or a PC-based split-screen setup—it doesn’t automatically combine two independent Moonlight streams into one session. For separate PCs, a hardware multiviewer is likely more straightforward.
I’ve used Moonlight and Sunshine for streaming games to a Deck, but the controller-routing problem is my main concern with running multiple game instances on one PC. Each controller needs to stay assigned to the correct game instance, which isn’t always automatic.
We’ve already worked through most of the popular local co-op games, including several LEGO titles, so an external multiviewer seems worth investigating. Spending a few hundred on a reliable low-latency model would still be cheaper than replacing the TV.