Over the course of the weekend I picked up a new multi-track audio recorder, a Zoom R8. Nice little standalone unit that definitely gets the job done.

There is one thing about it however that’s both good and bad. When taking power from an external source (it can run off four AA batteries for internal power), it only takes USB.

Why this is good: No “wall wart” adapter. Any time anything can be powered without the use of one of those, I’m a happy guy.

Why this is bad: For a laptop, you have to know which specific port to use in order for the unit to be powered correctly.

Modern laptop tip: Some ports are “always-on” while others are not

On my Lenovo ThinkPad E430 there are four USB ports. Three on the left and one on the right.

The right-side USB port is the only one on the unit that is an in “always-on” state. And what this simply means is that when the laptop goes into “sleep” mode, that port stays powered, whereas the left-side ports do not.

Most people use the sleep-mode feature on their laptops. However, if you’re powering anything via USB that isn’t connected to the always-on port when sleep mode engages, whatever is plugged into it loses power the moment that happens.

Where my Zoom R8 is concerned, it would lose power instantly and the audio project data would be lost when my laptop goes into sleep mode.

Where this information would matter for you is if you were charging a phone or a portable media player such as an iPod Touch.

One can easily assume that with something plugged in and charging via USB – even if the laptop is plugged into the wall – that when the laptop goes into sleep mode, the whatever-it-is connected via USB would continue charging. Nope. The charging stops when sleep mode starts…

…unless you use the always-on USB port.

Laptops differ concerning which is the always-USB port; your laptop manual will tell you which one is the designated port for that.

“What about PCs?”

As far as I’m aware, all on-board USB ports on a desktop computer always remain powered even when the OS goes into sleep mode, should you use it, but I could be wrong.

Do USB ports stay powered when a PC is in sleep mode? Post a comment with your answer.