HELP!! with INSPIRON 6000

 I have a Dell Inspiron 6000 that will not power on.  This occurs the same way whether the battery is installed or not.  I press power, and all lights momentarily light up.  Then all but the Power Indicator and the Hard Drive lights turn off, and the A light in a little lock sign flashes 10 times, then you hear the hard drive power down, and all lights shut off.
  What could the problem be?:emotion-6:[:'(]