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User profile for user: roroco1
roroco1 Author
User level: Level 1
11 points

usb-2 & usb-3 power issue

I need some technical info on using USB-2 on a MacBook Air with USB-3. The basis question is how much can I safely use and what is the best hub for the USG-2. All things may be going smoothly until I plug in the remote DVD player. Sometimes it just stops the computer; sometimes I get a notice to remove the unit taking so much power; sometimes it hums loudly! The icon never gets to the appropriate site. In short I can't use my DVD player. (this is the third one I've purchased.


How much USB-3 power (I don't know what else to call it) is put out and how can I find out if I'm overloading the circuit.

MacBook Air 13″, macOS 11.6

Posted on Dec 20, 2021 10:52 AM

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User profile for user: tbirdvet
tbirdvet
User level: Level 6
14,495 points

Posted on Dec 20, 2021 11:11 AM

USB ports can usually support 900ma. I have had some DVD drives that require two USB connections to power up. Many must be connected directly to the Mac and not through a hub. Many times if the hardware is drawing too much current you will get that fault message as you stated. I have an Apple Super Drive and always works fine connected directly to my Mac. I also have a Samsung DVD drive that also works fine on my Mac but requires two USB connections on my Windows PC.

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User profile for user: tbirdvet
tbirdvet
User level: Level 6
14,495 points

Dec 20, 2021 11:11 AM in response to roroco1

USB ports can usually support 900ma. I have had some DVD drives that require two USB connections to power up. Many must be connected directly to the Mac and not through a hub. Many times if the hardware is drawing too much current you will get that fault message as you stated. I have an Apple Super Drive and always works fine connected directly to my Mac. I also have a Samsung DVD drive that also works fine on my Mac but requires two USB connections on my Windows PC.

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usb-2 & usb-3 power issue

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