with the switchim1947 power your computer COMPLETELY downwith the switch on the back panel that is actually located on the power supply. I even unplug the computer. Then you need to remove the side of the computer case (this may be different by your specific model. Post some pictures of what your case looks like etc. Use this guide [guide|21499] for that. That way we can see what you see. Once your remove the case and can see the motherboard, locate the battery.
[image|1506591]
The battery may be secured with a little metal clip that you push aside with a small screwdriver. Then remove the battery with a small pair of pliers etc.