So glad I found this. Just bought an extended battery on ebay and had the phone plugged into the computer but it would not turn on. Have it plugged into the wall now and it it up to 10 percent charge right now and it finally turned on. Thanks.
If your Droid Bionic battery is completely dead, and you try to charge it using a USB from a computer, you will see the white light instead of the normal charge light. The phone MUST CHARGE TO 10% BATTERY FIRST, THEN IT WILL POWER UP! Do not panic, just be patient. For me, it took about 20 minutes or so.