USB power draw

Devryd · December 10, 2019

Not sure,whether it is the correct subforum, but how much power can I get from a normal USB Type A port on a Laptop?
Is 3W reasonable?

If not, do you have a different idea, how i can power a pump for my watercooling loop?

WereCatf · December 10, 2019

10 minutes ago, Devryd said:

Not sure,whether it is the correct subforum, but how much power can I get from a normal USB Type A port on a Laptop?
Is 3W reasonable?

The USB-standards specify that you can draw 500mA at 5V, ie. 2.5W, though in my experience many systems do allow you to draw up to 800mA at 5V, or 4W. Whether your laptop does allow for 800mA or not is up to your laptop, though. Also, your pump probably requires 12V instead of 5V, so even if the laptop did allow for 4W out of USB, you still wouldn't be able to power your pump from it.