And XP has issues with USB.
But I can answer about XP and USB speeds. In XP (not XP SP1 or later) the USB speed is version 1.0 or low speed. USB 2.0 speed was not enabled till later.
Why are you at XP and not updated? Is there a reason? Also, given no make, model and more of such listed in your post, I can check on things.
--> It is worth noting that Web cams are notorious for missing drivers. It's a common problem to find an owner that has a web cam with no make/model and for them to ask for help getting it to work. You know to nod and hope they figure it out.
Hello, I am using an old PC with windows xp. The Web cam(usb) not working with internet usb modem .Each one is 500mA Power and the power of each port is 500mA. If only the web cam is pluged in the port it is working.There are four usb ports in the cpu.I don't know the speed of usb root hub. In the devic manager there are three "usb root hub" seen ,the drivers are installed properly and no any yellow marks seen in the device manager.Please find a solution. Thanks