How to get an HP Elitebook 840 G4 on a Universal USB-C dock to be Thunderbolt compatible?

I have two laptop PCs:

1. HP EliteBook 840 G4 (for personal use)
2. Lenovo T480 (for work use)

My Lenovo is connected to a ThinkPad USB-C Dock Gen 2 (Type 40AS) so it can project to 2 monitors. I would like to use this dock on my HP EliteBook when I'm not using my Lenovo since based on the Product Page of the Dock, it's generic and should work with other non-Lenovo PCs.

However, I found out from the Product Manual that my HP's USB Type-C isn't Thunderbolt-compatible or doesn't have alternate modes: HP Elitebook 840 G4 Docking solution.

Based on that, it seems I may not be able to project to dual monitors using this dock, but I found that some other users were able to actually make their HP Elitebook 840 G4 work on a Universal Docking Station:

• “Reddit: HP Elitebook 840 G4 - USB C Docking Station Help”
• “Reddit: USB-C style dock with Elitebook 840 G3?”

As advised on the second Reddit post I've tried installing DisplayLink drivers but it still isn't working.

Is there any way I can "upgrade" my HP's normal USB-C or USB-A to a Thunderbolt Port? Perhaps via a software upgrade or a connector dongle/adapter?

Is there any way I can "upgrade" my HP's normal USB-C or USB-A to a Thunderbolt Port?

No, supporting Thunderbolt requires a Thunderbolt controller in the computer. You can't upgrade a port from USB 3.x to Thunderbolt with software or a dongle any more than you can upgrade a USB 2.0 port to USB 3.x with software or a dongle.

If all you want is a dock for two displays, 2 or 3 USB-A devices, and passthrough power to your laptops with USB-C ports then there are plenty of options that should be under $150. The laptops will have to support DisplayPort MST on the USB-C to find a dock in this price range with dual video support, unless you find a real deal on a DisplayLink dock.

I've tried the DisplayLink approach and updated the drivers but it still isn't working.

I'm not sure I understand. DisplayLink is a brand of USB to video hardware and you can't add DisplayLink to a dock with drivers. To get DisplayLink means getting a dock with the DisplayLink hardware in it. DisplayLink docks will require drivers to provide video, DisplayPort docks will not require drivers for video.

Don't get too hung up on "Thunderbolt compatible", I've seen this term abused into meaninglessness. All "Thunderbolt compatible" means is it won't burst into flames if you plug it into a Thunderbolt port. If a dock plugs into a USB-C port then it is by definition "Thunderbolt compatible", unless they really screwed up the wiring. Being "Thunderbolt compatible" is not the same as requiring a Thunderbolt host to work.

Also abused into meaninglessness is "universal docking station". As best I can tell is that this term describes a dock that can connect to laptops that may or may not support DisplayPort on its USB-C port, and may or may not have a USB-C port. They get video by using a DisplayLink chip in the dock. If you have laptops that support DisplayPort MST then using DisplayLink will likely be going backwards in video performance. Most any laptop with DisplayPort on USB-C will do better than DisplayLink can offer and for lower cost.

Thunderbolt docks (not "Thunderbolt compatible" docks) are often quite expensive because they require the bandwidth that only Thunderbolt can provide. A dock to get two video ports and 3 USB-A ports will not require Thunderbolt to work. Ignore the terms "Thunderbolt compatible" and "universal docking station", this is meaningless marketing speak.

Thunderbolt is a set of protocols that run over a USB-C connection.

Having a USB-C port does not mean your system can support Thunderbolt. In order to support Thunderbolt, your computer must have the Thunderbolt hardware controller. For laptops, this is usually an upgrade option when you first purchase the system, and cannot be added later because it is a physical chip soldered to the mainboard.

Another similar protocol is DiplayPort, which also has USB-C options. In general, these protocols each support the lower protocol (backwards compatible) but not the higher protocol (forward compatible). So a Thunderbolt-enabled computer can run basic USB 3.0 stuff, AND Thunderbolt stuff, but a USB 3.0 computer without the Thunderbolt chip cannot support any Thunderbolt systems.

Because your G4 lacks a Thunderbolt controller there's a slim chance it may support certain very limited aspects of the dock connection, but there's a better chance it will not recognize or support the dock at all, and even if it does support some functions, these will be limited.