If drawing to much power from the usb socket is the problem then you need to provide power for the arduino either by going through a powered hub, or if you are drawing to much power on the arduino to run it off usb switch the power jumper over on the board and provide power for the electronics on it seperately, rather than drawing it from the usb bus.
HTH
Nick
Hi HC,
I've had the problem of the USB bus being killed because to much power was drawn, but it was because I plugged a pot into the wrong ports.
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