Have a new 2018 13" Macbook Pro, receiving power from (and using) an LG 4k 27" USB C display. I'm doing a backup of a lot of big, older drives onto 4TB WD USB 3 portable drives. Something I've noticed: with this setup, I can run one of the WD portable drives and then whichever big drives I want to plug in to pull data from (they use an external power source), but I can't get two of the portable WD drives to mount while in this setup. Am I running into an available power issue? Perhaps from the LG monitor powering everything? Anyone have any other guesses?
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New Macbook Pro 13" having difficulties powering all four ports?
- Thread starter FrankieTDouglas
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Can you explain you drive set up more. You mention big older drives. Are these connect to the MBP? If so, are they also powered by the MBP? Also, have you tried connecting your portable drives via a AC powered USB hub? With this much drain I would not be surprised if you are exceeding the limits.
The setup: back left USB port is the monitor/power. Back right is a WD portable drive, powered by the laptop. Front right port is an external 3.5" drive, receiving power from an AC power source. Front left port is where I'm attempting to plug in an additional WD external portable drive, which would need USB power. I haven't attempted to disconnect the monitor yet and only use the USB C direct power plug, but it'd be a shame if this worked since that defeats the purpose of using a USB C monitor to power the laptop.
EDIT: just switched from monitor USB C power to the wall power plug. The WD external mounted fine. Which leaves me to believe that even though the LG monitor can power the laptop, it's not giving enough power to also mount external drives.
Which display are you using?
Not that it should really matter... even if the power supply cannot provide enough power, a MacBook should resort to drawing additional power from its battery rather than under-powering accessories.
Each side of the MacBook Pro should be able to provide 15W, i.e. 15W shared between the two left ports, and another 15W shared between the two right ports.
Not that it should really matter... even if the power supply cannot provide enough power, a MacBook should resort to drawing additional power from its battery rather than under-powering accessories.
Each side of the MacBook Pro should be able to provide 15W, i.e. 15W shared between the two left ports, and another 15W shared between the two right ports.