# USB cables with 2 connectors on one end **URL:** \ **Category:** Factual Questions\ **Created:** [January 19, 2010, 11:29am UTC](https://boards.straightdope.com/t/usb-cables-with-2-connectors-on-one-end/525547 "2010-01-19T11:29:38Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Random\_Design](https://avatars.discourse-cdn.com/v4/letter/r/58f4c7/32.png) [@Random\_Design](https://boards.straightdope.com/u/Random_Design)\ **Post date:** [January 19, 2010, 11:29am UTC](https://boards.straightdope.com/t/usb-cables-with-2-connectors-on-one-end/525547/1 "2010-01-19T11:29:38Z")
When I bought my external hard drive it came with a cable like this - a mini USB on one end for the drive, and on the other two regular connectors to put into a computer. One is labelled power and one data, however the data one seems thicker and more wirey - and if I plug only that one in a computer, the drive works fine. So if it works fine with one, why do they make cables with two USB plugs? Or… am I slowly damaging the drive by not using both connectors? ---
**Author:** ![\_Undecided\_Adrian](https://avatars.discourse-cdn.com/v4/letter/_/eada6e/32.png) [@\_Undecided\_Adrian](https://boards.straightdope.com/u/_Undecided_Adrian)\ **Post date:** [January 19, 2010, 11:37am UTC](https://boards.straightdope.com/t/usb-cables-with-2-connectors-on-one-end/525547/2 "2010-01-19T11:37:17Z")
The power that the drives need is more than some USB ports can handle; So on those computers you need an extra cable for addtional power. If the port on your computer can supply enough power, it should be fine, I don’t think the drive could be damaged. My external USB hard drive has only a single connector and worked on all computers I used it with so far. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [January 19, 2010, 11:54am UTC](https://boards.straightdope.com/t/usb-cables-with-2-connectors-on-one-end/525547/3 "2010-01-19T11:54:57Z")
Some machines - especially laptops balk at providing the full 500ma that USB is supposed to supply. The cable you describe should have a common ground, making it possible (where necessary) to plug the data side into the computer that needs to access the drive and the power side into a USB port on a different computer, or one of those USB wall warts. ---
**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\ **Post date:** [January 19, 2010, 1:01pm UTC](https://boards.straightdope.com/t/usb-cables-with-2-connectors-on-one-end/525547/4 "2010-01-19T13:01:31Z")
I used to have a scanner that could be powered by a double-headed USB cable like what the OP has, if the PC provided full power to all ports, but if you were using an unpowered hub, the scanner came with a wall-wart power supply with a USB socket to supply the juice.