Multi monitor support?

[kilésengati]

Can the display outputs be used simultaneously and is the Deck capable of MST?
Such features could make the Deck /w Dock a decent combo for productivity applications as well.

[kilésengati]

Originally posted by catbox:

there is an hdmi and dp-displayport

not mentioned if it can output simultaneously

And that's exactly why I ask. Hopefully, they will release more details soon enough.

[ReBoot]

Fact is, you can use a video output and the native screen simultaneously.

[jonahhw]

This would be really good to know. I've been looking at other docks, and a shocking number of them have multiple ports but don't support multiple "screens". My current desktop setup is 2 monitors, and I'd love to replace it with a Deck but I need to know that I'll still be able to use my 2 full size monitors.

[PupKai]

Hey just wanted to post an answer:

I tested out my steam deck and I was able to output two HDMI signals one display port signal and the steam deck screen simultaneously so it looks like it can actually end up powering three external monitors and it's screen at the same time.


The hub I use is the Anker USB c 13 in 1 hub.

[sion]

Sorry folks: Steam Deck + Dell thunderbolt 3 dock + 2 HP monitors = both detected but only one driven

[Kamel]

I am replying because this page is a top result for "Steam Deck Multi-Monitors" and contains misinformation. The Steam Deck does in fact support DP MST over USB-C and I have personally driven 3 external 1080p monitors in addition to the built-in monitor.

Today, when in "Gaming Mode" (default), only one monitor will be shown the game and interface, the others will be shown a black screen. In desktop mode, the desktop can be extended with unique windows on each monitor.

I do not know if there are any plans to add the capability of extending displays using Steam's "Gaming Mode".

[kilésengati]

Originally posted by Kamel:

I am replying because this page is a top result for "Steam Deck Multi-Monitors" and contains misinformation. The Steam Deck does in fact support DP MST over USB-C and I have personally driven 3 external 1080p monitors in addition to the built-in monitor.

Today, when in "Gaming Mode" (default), only one monitor will be shown the game and interface, the others will be shown a black screen. In desktop mode, the desktop can be extended with unique windows on each monitor.

I do not know if there are any plans to add the capability of extending displays using Steam's "Gaming Mode".

3x1080p, cool, but poor little thing. How does it perform?

[Kamel]

Driving multiple monitors in desktop mode has no impact on performance of the device as expected (and same for "gaming mode", though the extra monitors are black). That would be a different story if trying to run games on all 3 monitors though of course lol.

I would even argue it handles it much better than most laptops I've used since it does in fact have a decent GPU in it and most people use laptops with slow onboard GPUs (2d desktop performance is a thing, it's non-negligible)

Edit: I use the term MST here - which is a valid term, but might not apply to USB-C devices as I thought... seems the term to use may be MHL, but everything else is the same so I'll leave it as-is. I'm no expert, if anyone can clear this up it'd be appreciated!

The point of my post was mostly to validate Steam Deck stated specs of DP 1.4 with Alt-mode support is correct, and MST works (this is unfortunately not a given - sometimes the hardware is there but can't be leveraged due to lacking proper driver support or configuration. It wouldn't technically be wrong for Valve to advertise it if it weren't enabled, but they did the right thing and launched it in a well-functioning state).

I won't attempt a full MST lesson here, but the tl;dr is: Each DP port has Xgbps bandwidth available to it as determined by the DP version and the connected device (hub/dock) and connection quality. Each stream takes Ygbps based on resolution, color space, and refresh rate. This is the factor that determines how many monitors can be driven from that a single DP port.

From the specs page:
"USB-C with DisplayPort 1.4 Alt-mode support; up to 8K @60Hz or 4K @120Hz, USB 3.2 Gen 2"

[sion]

Originally posted by Kamel:

I am replying because this page is a top result for "Steam Deck Multi-Monitors" and contains misinformation. .

You mean different information? The fact that at that moment in time the Steam Deck would detect 2 monitors connected via a Dell USB C/Thunderbolt 3 dock and only display desktop on one is still a fact. Not misinformation.

[Kamel]

The fact that the Steam Deck supports at least 4 monitors is a fact, not misinformation.

[jonahhw]

Valve has now confirmed that the Deck Dock supports multiple monitors

[lin_mdotor]

Take into account that this only applies to Steam OS. In Steam OS desktop mode works like a charm.
But I tried myself with the official Steam Dock in Windows 10, and the DisplayPort monitor max resolution is 640x480.

[rdracr]

I had the Steam Dock working with multiple monitors in Windows 10 just fine. Then I updated the Steam Dock firmware and now the DisplayPort monitor is maxed at 640x480. I assume it's a bug that will be corrected.

[lin_mdotor]

Got a response from Steam Support, and they don't offer any support for Windows.

Originally posted by Steam Support:

We do not have any suggestions for you as we do offer support for Windows OS therefore, we don't anticipate the docking station working with it either.
A replacement will not resolve this but we can issue a refund if you'd like.

I ended requesting a refund, and buying a USB C hub with 2 HDMI outputs, that works perfectly on both, Windows and Steam OS.
This one from Selore&S-Global: https://www.amazon.es/gp/product/B09FXLZ1L3/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
It works with this one, but I guess that any hub with 2 HDMI outputs will work the same.

Not the ideal solution because cable management is much worse in this kind of hubs, but at least I can have 2 external monitors in Windows.

[kilésengati]

Originally posted by lin_mdotor:

Got a response from Steam Support, and they don't offer any support for Windows.

Originally posted by Steam Support:

We do not have any suggestions for you as we do offer support for Windows OS therefore, we don't anticipate the docking station working with it either.
A replacement will not resolve this but we can issue a refund if you'd like.

I ended requesting a refund, and buying a USB C hub with 2 HDMI outputs, that works perfectly on both, Windows and Steam OS.
This one from Selore&S-Global: https://www.amazon.es/gp/product/B09FXLZ1L3/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
It works with this one, but I guess that any hub with 2 HDMI outputs will work the same.

Not the ideal solution because cable management is much worse in this kind of hubs, but at least I can have 2 external monitors in Windows.

The Steam Deck isn't a Windows device to begin with, so I'm not that surprised, but for 99 euro I'd expect an USB-hub to be class-compliant.