My thumb drive killed my mobo

It probably wasn't the thumb drive. It probably was you. You had built up a static charge and it discharged thru you/the thumb drive to the contacts in the USB port. The thumb drive is passive; it has no power of its own. Is the outlet the computer system plugged into properly grounded? Get one of these and test it: http://www.amazon.com/50542-Receptacle-Tester-Improper-... Any hdwr store should cary one.

If you're lucky, the circuit that was damaged on the board may only be 'tripped'. I'd unplug the board from the PSU for a few hours and then plug it back in and try it again.

It should not be possible for you to damage the computer by plugging in a USB drive static discharge or not. What is more likely is that it was a coincidence that the computer failed just as you were plugging in the USB drive.

Don't you think it would be possible for the static spike to damage the board's southbridge where the USB interface is?

No, based on my experience of hundreds of computers in environments where they have got carpets and you get a shock just walking to and touching the filling cabinets, not one has had damaged that could be put down as to being caused by a static discharge via the USB port.

Your suggestion of removing the mains lead is a good idea though.

The computer may have been moved though by putting in the USB stick, Check that all leads are still attached and if they are all OK try opening the case (with the power lead disconnected) and remove and refit the graphics card and memory.

^ and how much did you pay for that electron microscope and elequipment to disect components (NOT all ESD damage results in instant death to electronics).

YES winter time, low RH yes you can discharge into a USB port and damage the MB.
It does not requir a carpet. The voltage built up is based on the distance (chart) between the dissemilar materials. Below several hundred volts you will not even notice - O and max voltage used on a MB is what +12V.

Seams like it was last year some case had a problem with their shielding on front panel USB ports and there were several posts dealing with pluging in device and reseting Computer - some damaged MB USB port. Don't remember about totally kill a MB, but yes it is possible.

We are talking here of an electrostatic spike that took down the entire computer, while I might concede that a electrostatic discharge may damage the USB port, I have never known one to take down the whole computer (apart from a lightening strike) , which is why I said that it is extremely unlikely that that is the cause of the computer not working and that shamusk913 should look at other reasons as to why the computer no longer boots such as a bad connection etc.

Disconnect the front panel from the USB motherboard headers. The metal of the USB connector is grounded so it should not be ESD. If its related to you plugging in the USB drive its going to be a problem with the panel, possibly shoddy wiring causing a short. Of course it is still possible its actually damaged the board

If he noted a electrostaic discharge than that was probably close to 1000V. If holding the Thumbdrive and inserting it the Discharge could have been to a data line, and while I'm NOT saying it did, I AM saying it is possible. And yes he should check system.

For Info - It is documented that you DO NOT have to draw an arc, or touch a component to damage it. The electrostatic field surrounding a charge can damage components. A typical charge (RH under 30%) and Bringing your finger close to a IC (NO arc) can damage the IC due to EM Field.

On an IC in a lab, yes I am well aware. Consumer electronics are not nearly as sensative, and connectors are designed with ESD in mind. The discharge would not go to a data line anyway, its going to go to ground. The potential difference is higher, and the physical seperation is less. Unless there is a wiring problem. And if there's a wiring problem ESD is irrelevant, as the wiring problem is the actual cause.

I know what you're saying, but he never said he noted an ESD in the first place. This is really about about the "is it common bit" and its not and should be impossible unless there's another problem. You're touching it to grounded metal well before the datalines get close to anything

I bought a new mobo and it won't post either. Everything is powering up but no post. When I took out the old mobo one of the standoffs fell out, guess it had gotten loose . I unplugged the front USB unplugged everything, reset CMOS. I'm getting pissed.

I would pick up a PSU tester and plug the PSU's cables into it to test if all the voltages are available that should be, and that they are at the proper level.. A multi-meter would be usefull too, but for now the PSU tester might be all you need.
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