Here's the deal. Many people can't get their USB to work proper since they don't know that Microsoft doesn't install the drivers for them. This fact and more is noted at http://www.usbman.com On top of all this, you can find where chipsets are an issue as well.
As to combo webcam and digital cameras, I have tried a few and the quality is about average. You should get it upfront what your return policy is. Most of these dual purpose cameras can overheat if you run them 24x7.
Bob
I am going to be purchasing a Centrios DSC-228 2 Megapixel digital camera. It is a 4-in-one, digital camera, web cam and has a video/audio thing as well.
I am wondering if I should buy it or not, I have Windows XP and I read in another discussion how on his XP it wouldn't work. I just really would like to get this camera since it is cheaper and has webcam & digital camera in one.
Any comments on how good the quality is or anyone who has bought it, do you have any complaints on it?

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