"USB Device Needs Power" with more than one external USB HDD

[Sese12345]

hey there,

I have one problem left on my El Capitan installation: USB 3.0 works fine with external powered USB drives. And additional I can plug in one more HDD without external power. Still everything works. But when I plug in another HDD without external power I get this message:

USB Device Needs Power
Connect "External USB 3.0" to a USB port on this Mac

The other USB drives still working. Because the built is all new, I can't really exclude mainboard or bios setup. I can exclude HDD failure - I tested it.

EL Capitan 10.11.5
GIGABYTE GA-Z170X-UD5 TH
32GB RAM DDR4
i7 6700K
NVIDIA GeForce GTX 970 4095 MB
bequiet Straight Power 10 - 600W

I used MultiBeast 8.2.3 and the Increase Max Port Limit USB Driver. I also set the USB HighCurrent in config.plist.

Someone with an idea?
Thanks

 

[powerpcg5]

USB ports can only supply so much power.
It's not a never-ending supply of current.

Pick another/separate USB port to use for the other hard drive, or get a powered USB hub.

 

[Sese12345]

USB ports can only supply so much power.
It's not a never-ending supply of current.

Pick another/separate USB port to use for the other hard drive, or get a powered USB hub.

It does not matter if I use one front and one mainboard usb or two front or two mainboard usb ports. And I think it's strange that the first (working) usb drive still works when the second gets its error.

And yes, I am also thinking about the workaround of getting a powered hub. But that will be what it is - a workaround.

 

[nobodynose]

It does not matter if I use one front and one mainboard usb or two front or two mainboard usb ports.

It does matter if the USB ports you use are on separate internal hubs - for example, your motherboard has the following array of USB ports (from the specs on Gigabyte's website):

Chipset+Intel® Thunderbolt™ 3 Controller:

• 2 x USB Type-C™ ports on the back panel, with USB 3.1 support

Chipset:

• 8 x USB 3.0/2.0 ports (4 ports on the back panel, 4 ports available through the internal USB headers)
• 5 x USB 2.0/1.1 ports (4 ports on the back panel, 1 port available through the internal USB header)

Chipset+GENESYS LOGIC USB 2.0 Hub:

• 3 x USB 2.0/1.1 ports available through the internal USB headers

So, provided you have at least one of your front ports connected to a header controlled by that Genesys Logic USB 2.0 hub, you have two independent USB buses, with more overall power to go around. This should also be true if you connect one of your drives (with an appropriate adapter cable) to one of the USB Type C ports, since they are on a separate controller.

 

[sohus]

I am having the same issue. Did anyone solve it? I read somewhere that taking the power off (disconnecting PSU) for 5 minutes make the problem dissappear but have to try it when I get home.

Can't believe that those internal controllers can't power two simple harddrives if there's like 10 ports available.

 

[Sese12345]

I am having the same issue. Did anyone solve it? I read somewhere that taking the power off (disconnecting PSU) for 5 minutes make the problem dissappear but have to try it when I get home.

Can't believe that those internal controllers can't power two simple harddrives if there's like 10 ports available.

I absolutely agree. Even my macbook can power two drives at the two usb ports - of course. I have not tried again until you posted today: what can i say - it works now with two harddrives (I don't have more here to try). And because the pc was disconnected from power in between, this could be it.

Thanks for your post!

 

[sohus]

I tried to unplug from power but didn't work. Also 'highcurrent' setting under 'devices' in clover configurator didn't work.

 

[sohus]

I was able to solve my problem by switching to a iMac 17,1 profile (instead of Mac Pro 3,1). This profile is much closer to my hardware spec (6700k).