Hypothetically speaking, let's say my PSU (Power Supply Unit) didn't have enough ports to add another SSD/HDD. Could I power my SSD/HDD via USB?

  1. Would it work?
  2. Would it still be efficient/would it affect performance on SSD/HDD?
  3. Would it still be possible to use it as the main drive in a computer

I know you should connect it to the PSU, but I just wanted to know for future reference when buying/upgrading PSU on a computer. By the way, I have a Corsair CX Series CX600M. Anyone know how many SATA connections it has?

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    You would need both 5v and 12v lines, so no. – TheKB Jun 6 '16 at 15:37
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    oen considerating would have to be volts. the USB is 5V. What wires go to the SATA power connector - a yellow and a red.. yellow is 12V red is 5V.. so does a SATA drive use both 12V and 5V. if yes then it'd involve some electronic wizardry if it was even possibly. but if SATA only used 5V then it may be trivial – barlop Jun 6 '16 at 15:38
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    @TheKB I remebmer that laptop hard drives take just a 5V. (minor exception being one or two weird panasonic toughbooks that take 3,3V) – barlop Jun 6 '16 at 15:38
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    It really depends on how power-demanding is the pariticular SSD you use and the type of USB port you use. Also, unless you managed to find/make a USB->"SATA-power" adapter and use it in addition to eSATA(->SATA adapter) or so, you'll likely be using a SATA->USB adapter/bridge, which would certainly affect the performance and the possibility as the main drive (it's possible, but tricky, to install Windows on a USB drive; not for Linux though). – Tom Yan Jun 6 '16 at 15:42
  • Anyone know how to check voltage of SSD – Matthew Correa Jun 6 '16 at 15:49

SATA connectors have 3.3v, 5v, and 12v connectors. Even though 3.3v is not commonly used, USB only supplies 5v. Even if you went with USB 3.1 with its 3A, Hard drives draw 12 Volts @ ~1 Amp and 5 Volts @ ~1 Amp when idle so ~17 Watts when idle. USB 3.1 supports up to 5v3A or ~15 Watts so even if you built an active converter, it would not work, even at idle.

Edit: In this answer I have assumed that it is a standard desktop drive connected via a standard connector. If you use a Slimline connector, µSATA, or a SFF-8784 connector, which do not use 12v, and found a drive with the correct amperage (less than 3A) then it could be possible to power a drive this way.

  • @GhostCyborg No problem, I hope you found it useful. – TheKB Jun 6 '16 at 16:12

Most laptop (2.5") hard drive and SSD only use 5v power and about 0.5A as this image shows Found on Amazon.ca a regular 500Gb WD Blue 2.5" 5400 RPM

Closeup of 1st picture but some high performance HDD does take 12v so it should work on most cases with an adapter like the 3rd image USB to 5v only SATA Power Adapter found on Amazon.ca

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