I suggest read my previous post instead worrying about registers.


Messing around with registers can crash the computer, corrupt data, and might damage some firmware of some component.

Electro - thank you for your concern. It's most likely that this MoBo will fail anyway so this is more of an interesting experiment to see if it USB does work again. If it fails, not to worry, I can easily replace the MoBo.

I'm marking this thread as closed. I've gone down the USB-PCI route with this and got a 3+3 (3 front/3 back) USB2.0 PCI card. Everything is working normally and the on-board USB ports have now been disabled. Normal service has been resumed. Thanks to everyone for their help, you've been really useful and informative.