Is the AC power consumed 0.00 watts when no USB devices are plugged in?
257475
My Kill-A-Watt shows 0.0 watts with the charger plugged in and nothing plugged into the USB ports.
1446522
It is powered by the USB port on your computer. There is no AC connection to worry about.
1669597
There is no direct AC wattage draw. The speakers draw power through a usb cable from your computer. i would imagine the power used is quite low.
329659
I would not be concerned as much about the system resources used as much as the power drawn. They pull ~500 mA each which can be a concern if your laptop has other usb devices plugged in as well. In my experience my old macbook couldn't handle the power consumption. I would suggest using a powered usb hub if you want to run from your laptop.
1529801
Only to power other USB devices. I regularly use it without power for hard network connection and USB drive.
1547062
It requires auxilliary power. USB won't power it. But it comes with a power pack.
1552695
It is powered by the USB connection and doesn't require an additional power supply. It is not wireless and must be connected with the USB cable.
492900
No. After use I unplug from electricity. I use this only once a moth to backup my computers.
2115004
Not sure, check with Targus (website FAQs); I am using USB for power from PC. Sorry.
1191296
The AC adaptor is not needed, it use the power from the USB3 which is adequate. However, it does have a mini DC plug that use 5 volts if you have to use the adaptor. I do not use this plug at all for this device or any other device that using the USB2 or USB3.
2038167
No. This device does not need external power. Direct plug and play ( like a thumb drive)
577168
I only use it with external power, but I believe I recall reading that it can not be powered by USB.
1482789
No AC power required, runs off of USB power. Bought it because it uses Visioneer technology which I've used in the past and liked. Would have kept my old Visioneer but not compatible with W7.
130276
Depends on the USB adapter. It rated to work with USB 2.0 power standards. 5V 500mA or .500A. I don't feel, see or hear any difference from using a 2.0 hub or a 3.0 hub. Sorry I don't have a usb power meter to confirm its actual power draw. In short if the adapter is rated for at least 500mA then yes. Its not dead silent. You will hear and feel the wind from it. Depending on the position of the fan you might hear some motor or mechanical noise.
23300
No. It gets its power supply from the raspberry itself. No need for external power
972743
Are you talking about the external HD receiving power from the computer? If so, no, all of its power needs are supplied by the AC adaptor.
1299746
Thank you for your question. This hub can function directly with USB cord connected. Power supply is not necessary when using low power consumption devices. Should you have any questions don't hesitate to contact us again. Thank you.