inspiron 1526 wont post or boot?

i have a 1526 inspiron  when powered on the fan starts the cycles on and off every few seconds. the screen remains black.  the only indicating lights lit are the 1st on left of three between the power button and home button, that looks  like a lock with a 9 in it.  also the first one n left near touchpad power indicating light  while the middle of the five battery light flashes every few seconds  HELP PLEASE