I am completely new to raspberry pi.I have a raspberry pi2 and have loaded the raspbian linux that came with it. Now i want to use my old sata hdd for which i have bought a 3.5 inch casing(which works properly.. connected to my laptop.) As soon as i connect this to my pi. the display goes and as sson as i remove it ti comes back. donno why this is happening. hdd is ntfs formatted. what do i need to do to make this work. please help

Edit: display goes means the screen goes black like it is turned off. i.e it looks as if the machine is off. but as soon as i remove the hdd the screen comes back on. it does not restart

  • You might want to explain explicitly what you mean by "display", since there are a variety of possibilities here. – goldilocks Jun 19 '16 at 16:33
  • Unless the drive has a separate power supply it won't work powered via the Pi. The USB ports might supply enough for a laptop 2.5" drive, but they won't have enough power for a 3.5" drive. – joan Jun 19 '16 at 16:38
  • the casing has its own powersupply. so i dont think its drawing power from the pi – Sujit.Warrier Jun 19 '16 at 16:39

This is a power problem.

For the Raspberry Pi 2, make sure your power supply is rated for 5V at 2A.

For external hard drives it is highly recommended that you use a powered USB hub as well.

  • it has its own power and i dont think its drawing power from the pi. but thanks ill check if the power is right – Sujit.Warrier Jun 19 '16 at 16:12

it has its own power and i dont think its drawing power from the pi

Just in case, try editing /boot/config.txt and add:

max_usb_current = 1

Contra Patrick, it does not matter how large or high quality a supply you use, without this set all models but the 3 will default to underpowering the USB ports, and things such as external hard drives will not work.

The (older) A/B models will not power such a device no matter what you do, and you must use a hub. The newer +/2 models should be fine with the setting above enabled, presuming there aren't any other high power USB devices attached (keyboard, mouse, wifi adapter are okay) and the total supply is >= 2A. If the device then boots with the red power LED flashing, your supply is insufficient; if you are using a charger plus microUSB <-> USB cable, try another cable. They are not all created equal.

You must reboot in order for this to take effect.

Although it is not documented there, you can find out more about config.txt here.


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