Lubuntu 3rd monitor on USB-C multi-hub

[nginmu]

Lubuntu 24.04.4 LTS (Noble Numbat)
Qt Version 5.15.13
LXQt Version:1.4.0

HP Elitebook 850 G3 laptop

I have the laptop’s built-in monitor plus one external monitor, attached to the laptop’s built-in external HDMI output. Extended desktop works fine.

I wanted to add a third extended desktop monitor.

I plugged into the laptop, a small hub which has a USB-C lead, two HDMI ports, several card readers, five USB-A sockets, a VGA output, a network socket and two USB-C sockets one marked for power and the other for data.

I plugged a USB-C power source into the hub’s power socket.

I plugged a monitor into the hub’s HDMI1 output.

I plugged mouse, keyboard, camera and USB hard disk into the hub’s USB-A ports.

After plugging in the hub to the laptop, I used lsusb in the terminal to see if anything had been added to the list of attached devices. These extra devices appeared after plugging in the hub:

[code]

Bus 001 Device 005: ID 05e3:0610 Genesys Logic, Inc. Hub
Bus 001 Device 009: ID 1a40:0801 Terminus Technology Inc. USB 2.0 Hub
Bus 001 Device 012: ID 05e3:0610 Genesys Logic, Inc. Hub
Bus 001 Device 013: ID 2109:0103 VIA Labs, Inc. USB 2.0 BILLBOARD
Bus 001 Device 019: ID 05e3:f12b Genesys Logic, Inc. HD camera
Bus 002 Device 003: ID 05e3:0626 Genesys Logic, Inc. Hub
Bus 002 Device 004: ID 05e3:0626 Genesys Logic, Inc. Hub
Bus 002 Device 005: ID 0b95:1790 ASIX Electronics Corp. AX88179 Gigabit Ethernet

[/code]

I ran lubuntu update to it’s conclusion.

I rebooted everything.

On restart, all the USB devices I had added to the hub worked fine, the camera was viewable, and the disk was fully accessible. The USB psu feeding the hub’s power socket showed 2W.

The monitor however, will not come on. It ‘scans’ but finds ‘no signal’. Nothing is appearing in LXQt Monitor Settings or ARandR.

The same hub and monitor combo works fine on my friend’s Windows 11 machine, and I have a vague recollection of previously having had it working on this HP Elitebook 850 G3 laptop with an earlier version of Lubuntu, a couple of years ago.

I’m sure I must be missing something simple?

[celticwarrior]

@nginmu

HP Elitebook 850 G3

Are you sure the USB-C port supports video output? Not all do and the HP Elitebook 850 G3 is old(ish)…

[nginmu]

Entirely possible - that’s something I’ve not verified. My vague recollection of having it working on this machine might well be wrong (I’m wondering if I did it some other way - there’s a VGA port on the other side of the laptop to the HDMI, maybe I had some kind of VGA→HDMI converter in there or something)

In fact typing this, that rings a bell..

[edit]

Happy Days

That must have been what I did - I found an old VGA lead in a pile of junk where I used to have my computer. Monitor’s got a VGA socket too. All working, I got 3 monitors now Thanks for the push in the right direction.