USB-C monitor connection fails intermittently

Since the monitor works normally on another laptop and you have already tried different cables, the problem is most likely on this laptop’s USB-C port, power delivery or controller side.

Try these checks:

1. Connect the laptop’s original charger separately while keeping the monitor connected through USB-C. If the connection becomes stable, USB-C Power Delivery negotiation or insufficient power is likely causing the resets.
2. Test another video-capable USB-C port if the laptop has one. Also inspect the affected port for debris, looseness or damage.
3. Open Control Panel > Power Options > Change plan settings > Change advanced power settings. Under USB settings, disable USB selective suspend for both battery and plugged-in use.
4. Open Device Manager and expand Universal Serial Bus controllers. For each USB Root Hub that has a Power Management tab, clear Allow the computer to turn off this device to save power, then restart.
5. Install the latest BIOS, chipset, graphics and USB-C/Thunderbolt controller updates from the laptop manufacturer’s support page. Device Manager may not provide all of these updates.
6. Temporarily set the monitor to its native resolution at 60 Hz. If that stops the disconnects, the USB-C port may be having signal or bandwidth problems.

If the issue continues while the laptop has separate power, especially if touching the connector triggers it, the USB-C port or its controller may need hardware service. Restore the power-saving settings if disabling them makes no difference.