Question about USB powered hard disk

[Hateshinai]

I have a portable hard disk that gets power from 2 USB ports ("Power" and "Power + Data"). This is a bit of a pain in the neck since my netbook has 3 ports, and obviously I can't just plug it into a hub. So I was wondering, if I plug the "power" USB cable into an "AC to USB" converter will the hard disk work? Theoretically I think it should, but has anyone actually tried to do it?

[Ivo]

I never tried it, because I'm fortunate enough that my HDD of that kind most usually does not require the 2nd USB plugged in, even when hooked up to a netbook (!). I'm pretty sure that connecting the "power only" USB to an outlet giving it "power only" won't do anything bad to it, it will very very likely work as well, but I can't try because I don't have any such outlets.

[Hateshinai]

I just plugged it in using only one cable and it seems to work anyway. That's weird... Thanks.

[Jimmy Yakapucci]

From what I remember, the cable is made that way for older computers that may not provide the necessary power on a single USB connection, therefore 2 must be used. If you have a newer computer running USB 2.0, you should be fine.

JY

[Ivo]

Great that you can just use the single cable! It should work practically anywhere.

Whenever plug it into a hub, you will definitively need to plug both cables in, and even then it may not get enough power, but the option is there.

Ivo.

[dentman42]

Should work. The reason for the 2nd cable is that the USB spec is for the port to supply 500mA. Many HDDs require more than 500mA especially during spinup, and probably some USB ports don't really handle 500mA either.

I got a Kenwood car stereo with USB. I managed to come up with one combo of IDE to USB and laptop drive that worked, but none of my 2.5" IDE to USB enclosures would. I tried a couple of external 2.5" drives and found that the Seagate Freeagent Go would work, but only if I used a cigarette lighter-to-USB adapter to provide extra power - otherwise the drive couldn't spin up. Once it spun up, I could disconnect the 2nd power connector and it kept working. (I decided it wasn't worth $70 to still have to use a kludge).

As the weather got colder, the hard drive wouldn't spin up when cold unless I was accelerating (like getting on the freeway) when I switched to USB. I ended up getting a 32GB USB flash drive after checking the specs on the hard drive and seeing that minmum operating temperature was 40f. Plus, the 32GB drives had just dropped to $60.