Keyboard Stopped Working

[htid]

I turned my computer on in the usual way just now and logged on as normal but then had to restart. After I did so, my keyboard is no longer recongised! The light for scroll lock etc. comes on so it must have power, but I'm not able to type and caps lock scroll lock etc won't turn on or off. It seems that it happens as soon as I turn the computer on because I can't even press delete to go into bios. I've tried different USB ports (at the front of the computer and the back, so obviously they're not connected inside) and nothing. I tried the keyboard on the PS3 and it works fine so it's not that which is broken. I've restarted many times, turned off and on, disconnected power fully for a few minutes...not sure what else to do, any ideas?

[3DWizard]

Quickest thing to do is to have a different keyboard connected to see if you can get that working. If not, its obviously not the keyboard itself. Make sure you have latest chipset drivers installed. Any changes to the system recently?

[htid]

Thanks for the reply...I remembered I can just take the CMOS battery out for a few minutes as a next step, and that worked. Not sure why it happened but there you go!