USB-C enabled classrooms?

[supportman]

I'm looking into the future of classroom AV installs and inspired by this post on Linkedin I'd like to enable 1 cable connections for teachers in classrooms.

 

Has anyone done a project like this yet?

 

Basically I'd just like a teacher to come in with a laptop and plug in a single cable to display on a board, dual screen, charging etc

 

So far I have bought as a test setup:

USB-C monitor - https://www.amazon.co.uk/Samsung-LS34C652VAUXXU-Viewfinity-Monitor-Webcam/dp/B0C8P9Q4YN?th=1

 

I am also trying some different docks:

USB-C Docks 

https://www.amazon.co.uk/UGREEN-Revodok-Docking-Station-Ethernet/dp/B0C857NJKX

https://www.amazon.co.uk/dp/B0CT2R87KY

https://www.amazon.co.uk/dp/B0D62D48FH

 

And finally 5M USB cable.

5M USB-C cable - https://www.amazon.co.uk/dp/B0DCS6TDB2

 

I'm yet to test all these, just wondering if anyone has tried this? Do USB-C cables have length limits? Any gotchas?

[drutt]

We've used 1 cable port replicators since 2010, originally it was HP docks and now its these: https://www.startech.com/en-gb/universal-laptop-docking-stations/usb3dockhdpc

 

We're at a point now where we've rolled out casting to our ViewSonics and even had some of our newer classrooms be casting only and it's bliss.

[chazzy2501]

yes: I use these.. HP USB-C Dock G5 

 

the cable can be replaced if broken.  power, network, picture sound and interactive... nice. £129 each 

 

it has full size displayport as well as hdmi so you can even use a dp to vga converter on it to retrofit anywhere. 

[andy_b]

For me, USB-C cable with PD and display over 3M have been a little un-reliable. 

 

Microsoft Surfaces seemed to hate them and never work, thinkpads were mostly ok.

 

Admitedly they were just a variety of Amazon sources cables, but 3M seemed to work the best.

[chazzy2501]

I've used 4.5m cables with the benq 83" TV (about max for display port alt-mode) as long as the cable has the correct e-marker chip all good.  (I have a usbc tester)  

 

 

 

[3s-gtech]

Yes, we did this in 2021. Lenovo USB-C Hybrid docks in all classrooms.

 

The cables are consumable items, so it pays to always have some in stock and they must be up to spec. We use OEM ones.

 

Aside from Windows+P, it works well.

[lparry]

We briefly looked into this and a few issues we ran into:

• Admittedly niche issue - we wanted a 'triple' screen setup for our staff (Laptop + Duplicated Monitor & Smartboard as the board is behind the teacher) without the ability for staff to start messing around extending displays etc. - Standard HDMI splitters seem to struggle with EDID information and constantly tried to send 4K resolutions to 1080p monitors. Solved via an EDID controllable HDMI splitter (https://amzn.eu/d/5WN3Eaf)
• Due to the multiple screens and the hole we dug for ourselves - we couldn't find a surefire way to set the screen order consistently so dragging between monitors was unintuitive.
• With our newer 16:10 dell pro laptops - the resolution defaults to 1920x1200 until changed per display.
• One range of laptops we have didn't support USB-C DP Alt Mode ruling them out

A lot of our issues were self made and I am sure there is a good way to manage monitors but I didn't find it and the teaching staff didn't like the idea of us stealing their second display so the idea stalled and went on the 'to look at later' pile.

 

Dock wise - we had good results with the Dell WD19s (reliable but slow to handshake with the device) and the Kensington SD4842P.

[chazzy2501]

oh man, triple displays are impossible... We tried docking monitors, so laptop screen, docking monitor screen and the monitor has a displayport output to 3rd display (tv or projector)... Pretty slick looking setup... 

 

No...Hell no.  Powerpoint is the worst bwgger for this. The behaviour is just too erratic and new staff just fail.

[mdrabble]

Just done this at the start of the term.

 

Dell WD19 docks, DP to desk monitor and HDMI to large interactive screen plus everything into the dock etc.

 

ive told the staff, once plugged in, to close the lid, so it works just like when they had desktops - so one less screen to mess with.

 

So far, only issue I’ve had is windows updates kicking in unexpectedly.

[gszech]

I can confirm that the 5m USB-C cable we used in our school works well. It's currently low in stock: https://www.amazon.co.uk/dp/B0BCWKYNHM

 

I'm testing this 5m cable: https://www.amazon.co.uk/dp/B0DCBLFGJY. The specifications are identical, and it seems to be of good quality. 

When you order, I'd recommend getting extra cables, as they tend to wear out faster than HDMI cables.

 

The two docks you've selected look good. The Anker is probably more than you need, but it's brand reputation is solid. The UGREEN dock will require a Windows Driver for the 2nd monitor to work (one monitor will work fine without the drivers)

I initially tried the MOKiN docks, but I had to return them because they would freeze after a few weeks of use.

[psydii]

Whether triple screens work is very chipset/driver dependant.  They were what I had been given a budget to deliver, but we found out pretty quickly during early evaluations of hardware that there were too many variables to make that a safe investment.  We were also burned as an early adopter of USB-C docks, but we've not had systemic issues with post-2021 USB C devices.

Here is some good info about the state of USB C in 2025:
 

How Long Can a USB-C Cable Be?

What is USB-C Power Delivery?

What is USB4?

USB-C Cables and USB-C Adapters from Cable Matters

 

And to wander off into the weeds away from problems unique to USB-C for a moment....

USB Type-C Notifications in Windows 11: OEM Configuration & Testing Guide (With references to bad ACPI driver implementations from vendors)
....
(How bad ACPI implementations can impact your experience: 

Deep DiveGitHub - Zephkek/Asus-ROG-Aml-Deep-Dive: A deep dive into the ACPI.sys DPC latency problems on Asus ROG laptops)

Edited September 25, 2025 by psydii

[supportman]

So after much testing and different direct cables, docks and laptops in classrooms I can pretty much say USB-C doesnt work reliably.

 

I think its the cable lengths really, many of ours are 5 or even 10 metre runs.

 

Also we found the cables are broken easily on the laptop ports and actual cables.

 

We've gone back to HDMI for now.

[synaesthesia]

Yeah, I generally wouldn't trust a USB-C cable of more than a meter especially if it's doing more than just power and a single screen - for that reason I prefer the idea of docks on desks, and avoiding HDMI socket fatigue on the screen. Laptops with replaceable USB-C ports aren't too difficult to source unlike HDMI.

However it's still a faff - we're mostly HDMI and we go through silly amounts of cables. We're trying to get staff to make use of wireless casting where possible, unfortunately this is rubbish on Promethean devices. Works great on our Viewsonic boards though.

[chazzy2501]

Passive usbc has a limit of around 4m, The longest cables I have are 4.5m and they work well (charge and picture).  The no.1 upset of usbc for me is dirt, contact cleaner works well.  (No.2 is AMD laptops)

 

Not all usbc cables are equal either, so low quality ones may bite. 

 

IMHO 4k screens over HDMI are rather more unreliable and I've had less issue with USBC. 

[psydii]

That's where we've landed a few years ago.  That said, the  USB-C docks with true DP-ALT Mode support, with AOC (fiber) HDMI->Board and USB Certified  cables spec'd for 20Gb/s 100W cables (with length <1m)  have proven, in the small trial (10% of classrooms) we've been running this year, almost as reliable as HDMI. While  I'm not ready to risk a large-scale deployment for now, we plan do a few room each year until we have the site back to the usb-c lifestyle. (why? because 15m AOC fibre is needed for reliable HDMI, and that is expensive and prone to damage - replacing USB-C is quicker, easier and cheaper, so it's a trade off, but if the helpdesk numbers start to swing the wrong way, we'll back-off sharpish)

 

Also pre 2022 USB C hardware remains a little hit and miss. Pre 2019 (intel/thinkpad) hardware had software weaknesses  that made it prone to  damage/failure, and this failure could be contagious. Post 2021 hardware seems to be resilient to the contagion. It's 2026, so the older hardware is getting retired and  a few years ago we made conscious efforts to move the older devices out from classroom teachers, or those likely to be using docks.

 

One thing that remains (and HDMI has this problem too) is that ports can become loose after a few thousand disconnect/reconnects.  However with USB C (on "good" laptops) you've got at least two ports available.

 

Looking to the future. Those mac book neo's might change the landscape. It will be interesting to see their compatibility.  

[forkies]

We found the actual USB C cable being the only issue we came up against when implementing USB-C docking stations in every classroom a few years back for staff. You have to get the right replacement cable if they get damaged, otherwise they either don't charge or don't run data, or sometimes both. We were buying replacements of a specific cable which we never had an issue with, however that cable has gone from everywhere so looking at buying a few different options to test before we bulk buy again. Initially we were running docks that ran the displaylink as the older laptops in our fleet didnt support display port alt mode, which added cost to certain areas, but I imagine most schools now have hardware that supports this natively.

[chazzy2501]

The cable on my docks is secretly changeable. (So you could go 4.5m USBC, straight to dock)

 

my quick vid on usb-c repair on the HP G5 docks:

 

[psydii]

a 4.5m usb c cable is not going to  support usb 3.2 or DP Alt mode.

[chazzy2501]

16 minutes ago, psydii said:

a 4.5m usb c cable is not going to  support usb 3.2 or DP Alt mode.

 

We use one almost daily without issue

[psydii]

Blatantly AI.    

What res/refresh rate is the screen? All our boards are 4k, so are quite fussy.

[Mr.Ben]

We've recently started putting Dell USB C docks into classrooms. We have Clevertouch screens in our classrooms.

 

In advance, we have had to replace all of the AV cabling as previously the school had an ad hoc approach with a lot of inconsistencies.

 

We have gone for 8k compatible Fibre HDMI cables - not cheap, but only a few pounds more than 4k.

 

We have blanked all of the usb ports as we can't get USB C functioning reliably.

 

We have used USB 2.0 active extenders to support touch, with a short usb a to b cable.

 

For consistency some classes do now have some excess cabling (hidden in trunking), and the cost is about £75 per classroom, plus £100 per dock.

 

Still significantly cheaper than PCs on desks.

 

 

 

 

 

 

 

[MatthewL]

I used 24" Lenovo monitors that had it all built into the screen and you can daisy chain 2 monitors together and only have to have the USB cable to the laptop.

 

What I did note was that there USB c cables are not all the same as some do not delivery power properly but we never had a need for more than 1.5m cables or what ever the standard was.

[supportman]

13 hours ago, Mr.Ben said:

We've recently started putting Dell USB C docks into classrooms. We have Clevertouch screens in our classrooms.

 

We have gone for 8k compatible Fibre HDMI cables - not cheap, but only a few pounds more than 4k.

 

We have used USB 2.0 active extenders to support touch, with a short usb a to b cable.

 

 

 

 

 

 

 

 

Would love to get some links for those cables.

[DrBeaker]

Many months later still NOTHING but issues since replacement of older working setup of PC with DP/HDMI with laptops/docks with USB-C.

Constant display issues, disconnections, weird sound issues.

 

Didn't have any say on the change except to say my predictions of unreliability with it I'd raised and were brushed off, unfortunately came to pass as truth.

 

Edited April 14 by DrBeaker

[chazzy2501]

Yes, I'd say that newer TVs that have native USB-C direct (like our benq above) seem to be very reliable..

 

I've found that introducing HDMI and 4K screens is where reliability has issue, adding a dock furthers the issue. We have in one room reverted to VGA (via DP) as we cannot fathom why the reliability was so poor.  (older clevertouch)