My Mac Pro was not starting up and the status light was just flashing. I tried everything I could think of including removing the battery as someone had suggested on one post and in doing so I snapped off the little metal clip that holds the battery in place. I read that the battery saves the date and time and that if your Mac has a problem starting up then to replace the battery according to the manual. At this point the date has been saved just fine and the Mac starts up fine. Is the battery really that necessary? Or is it like your appendix or tonsils to where you can live without them? If I need the battery what now? As an aside, it appears that it was either bad riser slots or two sticks of bad RAM that was causing my Mac Pro status light to just flash white and the Mac not to start up. I am not quite sure how I can tell if it is either the riser slots or the RAM that is bad. I took out the pair of 3rd party ram that was where the factory ram was installed and that had identical stickers on them to solve the "start up" issue.