Generic USB Webcam driver for XP

I have obtained a USB Webcam which is unbranded and has no manufaccturer
name on it. When I try to install it shows up as 'PC CAMERA' in XP, which
then looks for a driver but can't find one. I've tried various USB webcam
drivers from various vendors, but cant get them to work. Is there a generic
USB webcam driver I can try???