XPS 8940, storage device, USB overcurrent warning

Are you saying that device isn't usable or the USB port isn't usable, or both?

Was it a USB3 device connected to a USB2 port on rear of PC?

Have you tested this device on a different PC?

Do other devices still work when connected to that same USB port?

You can try clearing BIOS:

1. Reboot and start tapping F2 when you see the Dell splash screen to open BIOS setup
2. Copy down all current BIOS settings, to be safe
3. Power off, unplug
4. Press/hold power button for ~15 sec
5. Open case and remove motherboard battery (check Service Manual for details)
6. Press/hold power button for ~30 sec
7. Reinstall battery
8. Close up and connect mouse, monitor and keyboard
9. Reboot
10. Test PC with only that device plus mouse/keyboard connected to USB

If the port doesn't work at all and PC is still under warranty, contact Dell Tech Support for assistance. Have your Service Tag handy when you contact them.

The two USB ports on the XPS 8940 don't work with any USB, since the overcurrent warning. I did the complete power supply off, took out the battery, waited three minutes, put the battery back in an booted into firmware mode, refreshed the USB drives from firmware, then rebooted. They still don't work. There are three on the front bezel, the top two don't work, but the third does.

Too bad that didn't help...

Does that USB device work on another PC?

If this PC is still under warranty, contact Dell tech support for assistance. And if it's not under warranty, you can contact Dell's out-of-warranty repair service.

Yes, the usb storage does work with other hosts.  The two ports in question do not respond to any usb devices now.  The third port in front still works, even with the original usb storage device and did not receive a overcurrent warning.  I have contacted dell support and we are trying to work through it.  Thanks.

I will, assuming a solution is found.  After jumping through hoops, nothing has worked so far.  I would think that there must be a switch somewhere, all of the hardware tests have come up negative.

Post back and let us know what's done to fix this problem. That info could help other users who might run into this same issue...

Or maybe the USB power circuit for the front ports got fried and that might not be detected by the hardware tests you ran.

May not help, but open BIOS setup and disable the front USB ports. Save the change and exit setup. After it boots to the desktop, shut down normally. Then reboot again, open BIOS setup, and re-enable the front ports...

I think those two ports got fried.  I tried your bios suggestion, didn't fix the problem.  I guess I will get a usb c hub and plug it into the front usb c port.

A USB-c hub would be a work-around until Tech Support replaces your motherboard, assuming the USB-c port is still working...