My rear internal and front mounted USB ports have stopped working also my front mounted card reader lights up but is not being recognized. I did change the motherboard battery a couple of weeks ago and the BIOS seems to say all is enabled? Any suggestions would be appreciated.
As Technotiger suggests you may have disturbed some cables. The USB ports in the case are likely to be attached to USB headers on the motherboard, its possible that they have become loose or detached. The other possibility is that the CMOS values have changed by removal of the battery. Go into the BIOS and see if there is an option to "load defaults" if so you could try this. After replacing the battery did you have to reset the date and time? If so you will have lost your previous CMOS settings and that may be the cause of the problem in which case loading the defaults should correct this. Also look in the BIOS for an item such as "Integrated Peripherals" under which you should see the USB controllers, make sure they are enabled.