Surface Studio Laptop does not work with thunderbolt 4 display if not connected with surface charger

Question

When I connect my surface laptop studio to my thunderbolt 4 monitor without an external power source, it goes into a loop of connecting and disconnecting to my monitor. I don't think its my monitor as it works perfectly with single thunderbolt cable with both my Apple M1 Air and Lenovo ThinkPad. In both cases its able to charge and display with a single thunderbolt cable. This issue was previously reported by another user as well, I have linked that issue below.

Laptop Information: Surace Laptop Studio

Processor 11th Gen Intel(R) Core(TM) i7-11370H @ 3.30GHz 3.30 GHz

Installed RAM 32.0 GB (31.8 GB usable)

Device ID C1B7868F-0E88-4165-BAEE-B13DC6FA5266

Product ID 00330-80000-00000-AA344

System type 64-bit operating system, x64-based processor

Pen and touch Pen and touch support with 10 touch points

Monitor

LG 40WP95C: 39.7'' Curved UltraWide™ 5K2K Nano IPS Display | LG Global Business

Previous post related to the same issue.

Surface Laptop Studio Thunderbolt 4 display only works when surface - Microsoft Community

Answer 1

Hi Tommy1B,

Thank you for reaching Microsoft Community.

Just to make sure that we get the exact set up you have that is causing the issue: your LG monitor is connected to the Surface Laptop Studio through USB-C to USB-C, and it keeps on disconnecting unless you connect the Surface to its power supply, correct?

If yes, is the monitor connected also to its own power supply?

As mentioned on the other post, this is likely an issue with the power delivery on the USB-C port since both USB-C port of the Surface and the monitor delivers power to peripherals connected. Have you tried connecting the monitor to the Surface through the other input ports of the monitor like the HDMI or DisplayPort?

Kind regards,

Marrion

Answer 2

>> your LG monitor is connected to the Surface Laptop Studio through USB-C to USB-C, and it keeps on disconnecting unless you connect the Surface to its power supply, correct?

Yes

If yes, is the monitor connected also to its own power supply?

Yes

As mentioned on the other post, this is likely an issue with the power delivery on the USB-C port since both USB-C port of the Surface and the monitor delivers power to peripherals connected.

In my case, Surface studio laptop is connected to the monitor via usb-c and the power supply to the laptop is via the surface connect port.

Have you tried connecting the monitor to the Surface through the other input ports of the monitor like the HDMI or DisplayPort?

Yes. There are no issues connecting to the monitor through HDMI or DisplayPort.

Answer 3

Hi Tommy1B,

Thank you for the details provided and apologies for the delay in getting back.

This is likely due to power issues where the monitor would try to draw power from the USB port of the Surface even if it has its own power source connected and since the USB-C port of the Surface only supplies limited power, it causes the monitor to disconnect and reconnect. So, connecting the Surface to its own power supply would mitigate the issue.

As for this case, we recommend to just use the other connection to the Surface either through the HDMI or the DisplayPort ports of the monitor.

Kind regards,
Marrion

Answer 4

Thanks for your reply.

"This is likely due to power issues where the monitor would try to draw power from the USB port of the Surface even if it has its own power source connected and since the USB-C port of the Surface only supplies limited power, it causes the monitor to disconnect and reconnect."

This doesn't make sense at all as the monitor cannot possibly draw power from the USB-C, in fact the monitor supplies power to the laptop. Also I don't have any issues with any other thunderbolt enabled windows or mac laptops with the same monitor. I suspect this to be something to do with Surface's thunderbolt 4 port. Given more than one person has complained about this, this might need a bit more investigation.

Answer 5

Hi Tommy1B,

Apologies for the delay in getting back. We understand the sentiments and the understanding on this. I suggest reaching out to our live support for further assistance and also for us to do a remote session with the device for further investigation. You may reach out to our live support through these steps below:

1. Go to Contact Us - Microsoft Support
2. Choose how you would like to get support for your Surface device.
3. Type in the problem you need help with.
4. Look at any available solutions offered and select Contact Support.

In case needed, you may also check this forum article by Barb Bowman on getting phone or chat support: How to get Phone and Chat Support (for Surface Home/Consumer - Microsoft Community

Kind regards,
Marrion