So guys, is there any solution to this? I have here STM32F4discovery on my desk and i would like to power it externally. I have asked STM official to provide me solution for this. I have been told that there is problem with stlink pulling NRST of STM32F407VGT down if not connected to PC. So i have been adviced to remove NRST connection from stlink to F407VGT by removing SB11 connection.
But this didnt help at all. I am still unable to power discovery board externally.