Is there a limit on the amount of power my USB ports can handle? How can I check to see if mine are being used appropriately?
The general amount of power that most USB ports can handle is 500mA (milliamps). It is a good idea to check the status of your ports every once in awhile to make sure that you’re not over exceeding the power that they can endure.
If you don’t check on this regularly, you could be setting yourself up for a USB power crisis and no one wants that! You use your USB ports for several of your devices and you may just not realize how much power all of those things are taking up.
For example, you may use the ports for your digital camera, cell phone, your mouse, the keyboard, a Web cam, a music player or others. If you have several of these devices running at the same time, they’re fighting for the power and if a port is overwhelmed, it could completely shut down. Along with your USB port being damaged, your devices could end up being at risk too.
To check the power demands on your ports, you have to go through the Device Manager. If you use Windows XP, right click on the My Computer icon and select Properties. Then choose Hardware, Device Manager.
For Windows Vista, click Start then right-click on Computer, select Properties and choose Device Manager.
Within the Device Manager box, double click on the Universal Serial Bus controllers (it’s the very last item on the list). Next, you’re going to double click on the first line that says USB Root Hub. There will be multiples of these, but click on the first one listed. Now, choose the Power tab.
Under the Attached Devices area, you will find a list of all the devices you have running through your ports right then. You will also be able to view each one’s power requirements (in milliamps).
As mentioned above, a port can handle up to 500mA, so if one of your root hubs is close to that 500 mark, you need to switch around some of your devices to other root hubs, so everything isn’t all filling up on one.
You can also connect another hub to your PC if you have an available port. There are hubs available out there today that can turn one port into four or even more. So, if you’re close to overloading your root hub, you may want to look into something like that as well.