If you read the USB spec, you can short out the USB 5V lines to any other line without burnout. And at 500mA at 5V that's 2.5 Watts. This should not strain any machine's 300 and up Watt power supply.
I'd look eleswhere for the cause such as age, etc.
Bob
My daughter left her iPod Nano plugged into our emachines running XP all night long. When we rebooted the computer in the morning - we get little or no power. The computer seems to start up ok, the light turns green, then you can hear the power quieten down & the light fades to a pale yellow. Nothing works from that point on.
Is this the power supply that has burned out or does someone know what else it could be?

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