Nuked my Uno USB Serial Port

It looks like i have nuked the USB serial port on my Uno.

When I plug in I get power but nothing appears under Port in the Arduino IDE, unplugging and plugging in another Arduino then shows the port for that device, switch back and again no port.

Any good test to show that it is dead, and if so, can I use an FTDI USB dongle to program the Uno via the TX and RX ports or will somehow the dead USB Serial interfere with that?

try the loopback test? ISP on the chip?(I take no responsibility) Does the device show up under Device Manager (on Windows)?

Loopback test won't work as there is no port to choose that represents the Uno.

If I have nuked part of the USB, which still allows power through, just the data part not working, any ideas about where on the board I should look to be able to replace any blown part?

The little teensy chip next to the USB connector. Try reprogramming it before you try remove & replace. Search "16U2 reprogramming"