WD Elements 500GB: Minimum current


I’m thinking about buying an unpowered USB hub to split a single USB port in order to run two separate 500GB WD Elements hard drives. Both hard drives are USB powered only.

Can anyone tell me the minimum required amperage that a single 500GB WD Elements requires to function properly?  Most USB 2.0 ports output a maximum supply of 500mA, which would split to equal 250mA for each hard drive. Would that be enough power?

WD recommendations are always to avoid hubs for USB-powered drives. The length of a single cable needs to be less than 18 inches, as well. I think you would be inviting trouble by connecting two drives to a single port.

Okay. I realize it isn’t ‘reccomeneded’… but that still doesn’t answer my question. I bolded it for a reason.

I don’t know that anyone will be able to give you a definitive answer, assuming no one has tried with this drive model.

However, most of these HDD’s tend to be labelled 450mA, some 2.5’s can be 750mA but I doubt you’d find them in an external enclosure. I expect if you tried to spin both drives up at the same time you’d have issues, you might perhaps get away with it if you did a staggered spin-up but it seems risky. You did specifically state USB2, but it seems a lot more likely to work if you can manage a USB3 port…

These drives are quite sensitive to power and far to many computers have barely adequet power supplies before you start powering USB powered items. Personally I wouldn’t use a USB powered drive unless absolutely necessary a powered on is a better choice as far as I’m concerned.


Asus motherboards like mine, and probably other brands, have a feature which boosts the power available at at least one USB port to allow rapid cell phone charging. I don’t have a cell phone, so I’ve never tried it. In addition, I think it requires AI Suite 2, which I found to be a troublesome and unstable utility. It also took more than a simple uninstall to completely remove it from Windows. It’s really a shame, as the fan control part of the suite was very useful. It lets you change profiles without rebooting.