How much power does the G4 USB deliver?

eliaz · 01-30-2008, 11:03 AM

Hi all!
How much does the usb ports on the G4 deliver?
I want to add a WD digital passport harddrive to my setup, and that disk is getting it's power from the usb port. This is what i have connected to my usb ports on the G4:

A 7 port hub -> Powermate, OBD unit, Usb wireless adapter, Bluetooth dongle and sometimes a memory stick.

Can I add that harddrive to my setup, or will it be too much for the Infill?

makman · 02-07-2008, 11:14 PM

Per the USB standard 500mA at 5V per port. Sounds like you are pretty maxed out as it is, but I did open mine up and reviewing the pictures I took, it looked like Maxan put in a PTC "resettable" fuse. They are nice because they don't break then just increase current limit until the load is removed. They are fairly inaccurate so you might get more current out than the 500mA. The best thing to do is to get a current meter and measure how much current you are using now and then measure the hard drive alone. Add the two up and if it is significantly over the 500mA you are probably in trouble and will have to distribute the load across other ports or power the hub externally.