Backfeed to the USB port at the PC, not the supply from the PC to the 'duino..?
Check the true current consumption by getting a multimeter set to mA between the supply and arduino (put it between VIN pin and the supply).
Backfeed to the USB port at the PC, not the supply from the PC to the 'duino..?
Check the true current consumption by getting a multimeter set to mA between the supply and arduino (put it between VIN pin and the supply).