Portable USB-C Monitor Help

[squatman]

Hi,

I have an HP Elitebook 830 G11 (2 Thunderbolt™ 4 with USB Type-C® 40Gbps signaling rate (USB Power Delivery, DisplayPort™ 1.4)) and I'm trying to connect a USB-C portable monitor.

With no external power into the laptop and no external power into the monitor I should be able to connect a single USB-C cable between laptop and monitor, but it doesn't work. The monitor fires up but states no signal, the laptop doesn't detect a display but eventually gives me a message along the lines:

"The last USB device connected wasn't recognized" and in Device Manager under "Universal Serial Bus controllers" I have a grey icon "Unknown USB Device (Port Reset Failed)".

Interestingly it works fine with the same setup on my Dell Precision laptop.

Please see attached image for scenarios tried and results.

I suspect my HP isn't supplying enough power out of the Thunderbolt ports.

I've tried:

• Both ports on laptop
• Unhidden USB settings in advanced power settings and disabled selective suspend setting
• Under "Universal Serial Bus controllers" in Device Manager under all USB hubs > Power Management unticked "Allow the computer to turn off this device to save power"
• Ran USB test in startup diagnostics utility
• Installed latest BIOS
• Installed latest drivers (also via HP Image Assistant)
• Uninstalled graphics driver and installed latest
• Shutdown, disconnect all cables, hold power button for 60 seconds and turn back on
• Shutdown, disconnect all cables, hold power button & F6 for 20 seconds wait 5 seconds and turn back on

I don't have another USB-C monitor to test with. I do have a USB-C dock that can have a HDMI and/or DP monitor connected, but the monitors and dock need external power.

Any ideas or solutions would be greatly appreciated.

[banhien]

@squatman 

Sounds like your USB-C monitor does NOT support Thunderbolt™ 3 or Thunderbolt™ 4

Regards.

[squatman]

Banhien, it works perfectly when connected to my Dell laptop that has Thunderbolt 3.

[banhien]

@squatman 

Sorry, I don't have a USB-C monitor to test. Does your monitor have DP port, you cab use USB-C to DP cable to connect.

Regards.

[squatman]

It has HDMI and USB-C.

I just think the laptop isn’t getting full power/speed to the Thunderbolt Ports.

Where in the laptop could this be limited?

also can I completely uninstall thunderbolt and reinstall?