Using a USB hub won't solve the bandwidth problems. The two USB ports may be connected to the same connection internally. Some motherboards have two external USB ports running off of one USB connection on the motherboard. This means that both the modem and webcam would be fighting over the same limited bandwidth. A hub would just be one more device between the PC and webcam and modem. If it is USB 1, then it really won't have the bandwidth for a modem and webcam.
Adding a second USB card is pretty simple and would probably solve the problem just because you could put each device on completely separate USB connections. If you are comfortable with a screw driver, you should give it a go. Let us know, and we can walk you through it.
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Think you got it right goates....
Okay should I decide to go shopping, tell me exactly what I should be buying and also if you need anymore information about my pc.
I am eyeing the toolbox............