Uno board smoked laptop dead help!!!!

I was trying to get my new uno board up and running and for a few seconds it worked.
Suddenly saw smoke coming from it and immediately unplugged from my laptop but not before my laptop completely died.
Omg What happened!!
I need this laptop!
Please someone tell me what happened and what I can do.
Thank you

We don’t know what happened.
Maybe a short.
You tell us.

Try restarting the laptop without the Uno connected.
My laptop will declare "Power Surge detected" and shut down the port, resetting the laptop brings it back up.

Measure your Uno between 5V and Gnd with a multimeter set to ohms. If it's really low, then you may have a short on the board, or a blown component.

Ok thanks.

Thank goodness my laptop is working again. Scared me to death that I toasted it.
Can’t understand why this brand new board failed. Ordered a new one.

Checked resistance from 5V to ground.
243 ohms


That shouldn't cause a problem as it would draw a low current. Maybe some component is breaking down under load?

I'd be tempted to power it from a 5v adaptor to see if it burnt out completely.

It would be safer for your laptop / PC if you used a USB 2 'powered' hub for your Arduino so it doesn't draw anything from the computer.

It would also help if your computer has USB 3 ports as some of these ports give odd problems on the Arduino.


Did you have anything connected to the Arduino.?
Was it a genuine Arduino UNO ?

Thanks Peter. Sounds like good advice.
All I know is that I had both a 12 vdc power supply and my laptop plugged into it..

Yes I had 3 servos plugged in to the board.
My other arduino uno ran the same servos without any problems. I also had 12vdc powering it and it was plugged into the lap top.
I’m not sure if it was a legit arduino board. Sure looked real.

You were trying to run three servos off the on-board regulator, that was already burning off 7 volts?