This high-performance Thunderbolt ™ 3 adapter lets you add two 4K 60Hz HDMI monitors to your Windows ® or Mac computer through a single Thunderbolt 3 port. Energy, Climate Action & Sustainability.Maybe closing your laptop screen might help you get all 3 to be external? I dunno, just thought that I'd mention it. I'm not sure if it's actually the mux switch thing though, but one big difference I've noticed between our laptops is that mine in Windows will say that the external monitors are connected to the Quadro dedicated GPU, but his will always say that the external monitors are connected to the integrated Intel GPU no matter what he does or port he uses. It sounds like you're trying to do all 3 over USB-C and having issues, so maybe it has something to do with your integrated graphics not supporting 3 displays, or if you have dedicated graphics then maybe your laptop doesn't have a Mux Switch. I think we figured out that his laptop doesn't have a Mux Switch to switch graphics to the dedicated GPU and runs everything external through the integrated GPU, while my laptop does. My brother has a Dell Precision 5560 with a Quadro T1200 and a Dell TB4 dock, but has weird issues getting multiple monitors working how he wants. Two connect to the dock with HDMI, one connects with DisplayPort, and one connects with a USB-C to DisplayPort cable to the TB3 passthrough port on the front of the dock. I have a Lenovo P15 Gen1 with a Quadro T2000 and use a Lenovo TB3 dock to display to 4 monitors through one TB3 cable. but for now, the Thunderbolt 4/USB4 hubs on the market don't do this. The solution to this is MST, or multi-stream transport, which allows you to take one display stream and split it. When you try to add a 3rd monitor, the host no longer has any SST endpoints to assign to it, so it fails to light it up.

It handles dual displays by taking those two streams, and routing them independently through the Thunderbolt tunnel.

The Thunderbolt system routes those two via something called SSTs (single stream transports). You get two pipes into the Thunderbolt host. Thunderbolt 4 mandates that each Thunderbolt 4 controller (inside the host PC) supports two display inputs from the system's Display Controller (ie the Graphics Card).Įach of these are conceptually like the DP or HDMI port that comes out the back of your GPU. Yeah, the reason for this is because of architectural limitations in the way that Thunderbolt and USB4 implement multi-monitor support. Is there a technical limitation why I can't run 3 1080p monitors off of a hub like this? (4k is double 1080p in each dimension, x and y).

I assumed that 3 1080p monitors would be less demanding than 2 4k monitors, but it seems like this doesn't work.ģ 1080p monitors are technically fewer pixels than 1 4K display.Ī 4k display is 4x the number of pixels as 1080p.

Hdmi to thunderbolt 3