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I am trying to connect a 2 Tb external Hard drive (ADATA HD710) to my raspberry pi, but the problem is that when I connect it to one of the USB ports, the raspberry pi stops working. I am not sure if this is for the current (I have a simple charger of 5V - 2000 mAmp), or maybe I have to do an overclock or something like that. I would appreciate any suggestions to solve this problem, I tried to look for the current specifications of my external hard drive but I couldn't find anything, thanks

marked as duplicate by goldilocks May 28 '16 at 23:38

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  • I would suggest using a powered USB hub. This would eliminate insufficient current as a cause. Overclocking, does not apply here. – Steve Robillard May 28 '16 at 21:08
  • Do you have max_usb_current=1 set in config.txt? If not please read raspberrypi.stackexchange.com/q/32873/5538 and let us know if that solves the problem. Unless you have a bunch of other USB devices attached, that + a 2A supply should be fine. I've done it 24/7 ever since the B+ came out. – goldilocks May 28 '16 at 21:33
  • However, I have noticed it fails with some usb cables (and in other circumstances), so if it still doesn't work, keep trying cables until one works or you run out of cables... – goldilocks May 28 '16 at 21:36
  • I connected an usb hub, now the raspberry pi doesn't stop, but the disk is not recocknized with sudo blkid – Delfin May 28 '16 at 21:44
  • Are you using X or are you in commandline only? if your power starts to brownout, in X you get an RGB colour box appear on the screen. – KDM May 28 '16 at 21:52
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It sounds like your RPi and the HDD is not getting enough power. Normally, a 2.5 inch HDD (like HD710) requires 5V 0.6A (or even up to 1A) (nom.) power to function properly, so you only got another 1A for your RPi 2, which still not count the headroom for your PSU (some bad quality PSU may not deliver 2A as the spec). If you connect other peripherals to your RPi via USB/GPIO, your available Amps will be lower. Most importantly, HDD requires spin up and we should also take the spin up current into account.

I suggest you to have your firmware switched to 1.2A USB power and use a powered USB hub to power the HDD, or use a Y-usb cable with a separate power supply (you can make one by yourself too).

However, I DO NOT SUGGEST you to overclock your RPi, as it made the RPi requires more power, and also introduce instability problem provided that your Pi already did not have enough power.

  • Rubbish! Virtually all modern USB HDD run on <500mA. If they didn't they would not run on any computer with a compliant USB port. Some older (very old - usually PATA devices) need more, and usually come with a Y cable (with 2 USB connectors). – Milliways May 28 '16 at 22:52
  • ...Or simply a USB 3.0 cable, like HD710 – Kong Chun Ho May 28 '16 at 23:36
  • Also, other than on the 3 the total max current to the pi is limited to 2A by a polyfuse, so there's no point in a 3, 4, 5, 10, etc. amp supply -- despite recommendations by the Foundation and others to use a 2.5 A supply, which I think was just to hedge a bet on the quality of power supplies. – goldilocks May 28 '16 at 23:37
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    I don't think a 2.5" HDD requires 1A minimally, but I think a lot of them may require more than 500 mA even if they are "2.0 compatible", and 3.0 devices could expect 2+ amps. I also am not so certain the Pi's own USB ports are individually regulated to anything @Milliways Quick read from almost 10 years ago in which an OEM admits they don't publish current consumption stats because... – goldilocks May 29 '16 at 0:28
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    ...they essentially can't keep up with their own products, which I would take to be a a veiled way of admitting "We don't want to say they draw too much current". AFAICT the same practice applies today. – goldilocks May 29 '16 at 0:28

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