3.5" USB HDD Enclosure - USB Powered?

[watercooled]

Oh I wasn't implying they don't exist, nor was I denying they would work at least on some systems; just in regards to why we don't see many of them, it's likely it's related to the power spec and not wanting to breach it.

I've even known 2.5" drives to restart intermittently on some systems, although mostly through crappy front panel connections which seem to be plaguing systems nowadays. Unstable power can obviously cause problems with drives, and increasing the current over what was already an iffy connection isn't going to improve things. It may say USB3.0 on it, but people are still going to plug them into the even-lower spec'd USB2.0 ports. It's likely there's no power negotiation going on with the linked device (you can't negotiate over-spec after all), so it will probably attempt to power up all the same on a 2.0 port.

I'd just advise caution using them, and checking the drive's power consumption in review wouldn't be a bad idea; 7200rpm and higher platter-count drives are something I'd be especially careful of. And stick to 3.0 ports where possible.

[micre23]

Thanks for your input, the manufacturer also advises USB 3.0 if using 3TB HDD's ( I suspect this is due to their higher platter-count )