I just also started looking into Thunderbolt 3 docks after only getting 4k30hz. $400+ CAD is so much though! Im curious if anyone here has recommendations
After trying out 4 of them for the past year, the only TB3 Dock I recommend is the CalDigit TB3. Works great for 4K@60 and has every port I need for my media production needs.
One was a 'dongle-style' one, I forget what brand, that I got off eBay. It worked... sorta, but it would get really hot and the screen would sometimes just go blank and require a full reboot of the computer to get back (unless I unplugged it).
The other one was mostly okay, but didn't have many ports and would also have weird issues when my computer was in clamshell mode — the Elgato Thunderbolt 3 Dock. It was mostly okay, but every week or two there would be a weird issue that I just don't see using the CalDigit model.
It depends on the configuration you're interested in, but there are some _relatively_ inexpensive ones from Monoprice [0]. I've tested this one with dual 4k monitors @ 60Hz, and USB 3. It works reliably, which is the most important aspect for me. No laptop charging and fixed TB cable however.
Note that this working will depend heavily on what usb-3 peripherals you're plugging in, and the exact resolution of your 4k monitors.
a display at 3840x2160@60hz will eat up about 19.8gbps. Two of them together will use 39.6gpbs.
Thunderbolt 3 only supports 40gbps. So if you have peripherals that need anything more than basic mouse/keyboard (in my case, a decent webcam and a usb to ethernet adapter) this setup will fail.
I'm no video expert, so correct me if I'm wrong, but I thought you can do 3840x2160@60Hz video with 24bit/pixel with under 14.4Gbps, which is the HDMI 2.0 limit [0].
According to this [1], that signal would require 12.54Gbps, so with a link budget of 34.56Gbps - 2*12.65Gbps, you'd have about 9.48Gbps left over for USB and ethernet (which is on the PCI bus for this particular hub). I suppose these numbers include coding overhead for the physical link, but I can't say for sure. If you wanted more than 60Hz or more than 24bit/pixel, you'd definitely run out of bandwidth with two monitors and USB/ethernet.
If you don't already have the 4k monitors, just get one with a thunderbolt input/output. A slightly more expensive dell monitor with good thunderbolt/usb-c support basically replaced my $300 dock, and it only cost about $100 more than the cheaper 4K monitors. Mine takes thunderbolt input, provides one usb-c port, and 4 usb-3 ports. Daisy chaining is supported, but note that you can't run 2 4k@60hz monitors with peripherals on a single cable - see details below.
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Your setup needs will also depend on whether you plan to run two monitors with 4k@60hz.
I was trying to run a setup that would give me two secondary displays plus peripherals on a single thunderbolt cable, but the unfortunate reality is that it's just not fast enough.
Thunderbolt gets you ~40gb/s. A 4k@60hz monitor needs ~19gb/s, and a usb-3 hub will need another 10gb/s.
Two monitors + a hub means you need ~50gb/s and the connection just doesn't support that.
In windows things will almost always gracefully degrade (one monitor will drop to 4k@30hz). In linux... it's a bit of a grab bag depending on the order the devices are detected - Sometimes one monitor will fail to be discovered at all, sometimes usb devices will never be powered up, in some cases you'll see one (or sometimes both) monitors come up but no longer offer the correct resolutions.
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Once I realized I was hitting the throughput limits on the cable, I caved and moved to a setup that used two thunderbolt cables plugged into the laptop.
I'm fortunate that my work and personal machines both have two thunderbolt ports (mac work work, xps 13 for personal) and they can both be charged from the same cable.
4k@60 is ~16 Gbps per 4k@60 display over DP; USB3 is happy with 5 Gbps; 10 Gbps is USB3.1.
There were TB2 docks (i.e. 20 gbps total) that were able to handle one 4k@60 display, 1 gbps ethernet and usb3. I'm using such one (Kanex TB2 Express) with 2015 mbp.
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On PC side, thunderbolt is handled by firmware, operating system has on say on it, it just sees devices pop on pcie bus (on Apple side, it is by Apple-supplied drivers). So the handling should be same for Windows and Linux. One of the few things it can do is configure security policies for TB3+.
A lot of the usbc hubs only support 4k30, or have weird power delivery limitations/incompatibilities. I didn’t want to gamble $300+ on a hub that might not work.
My solution was to use an LG thunderbolt monitor (which has a usb3 output), and hang a cheap self powered usb3 hub off that for all the lower bandwidth peripherals.
This has worked well between Mac and pc so far, just one cable that does 4k60, 100W power delivery and handles all the other peripherals in the background.
One gotcha: Apparently some monitors deep sleep options mean the monitor powers down the hub and laptop won’t wake up from keyboard/mouse events!
Hopefully via usb4 thunderbolt can be commoditized and we can get cheaper universal hubs rather than a $300+ dock, but at the moment you need to spend a huge amount to do anything with multiple thunderbolt connections.
I've looked at the Dell WD19TB, after using the previous gen Dell one from work. But I don't know about 4k support, since I only use 2560x1440 screens, which seems to work fine.
EDIT: Ah.. I saw now it was well above 400 CAD from Dell Canada
I just plug both computers into the monitor, and switch the keyboard with a $5 USB switch. (Actually, I stopped using multiple computers a few years ago, but that's what I did back then.)
