Hey, I have been experiencing this problem for a while now, after sometime my usb keyboard would stop responding and then at times I would hear a "found new hardware sound (tun tun?) and it would start working again and when it won't, unplugging it and plugging it back would make it work. It has started to annoy me now, also sometimes it doesn't work on boot up and I have to restart my computer. I've tried installing different operating system too, first xp and then 7 and the problem is still there. My usb ports work fine for other components, e.g my cam, usb soundcard, i even tried changing the port for the keyboard but it would do the same thing and it's only the keyboard that does that, i've tried a different usb keyboard too. same problem. Any ideas/help would be appreciated!