A few things to try:
- Pull your cmos battery, laptop battery, and hold down the pwr button for 20 secs to reset the cmos and try again.
- Remove the laptop battery, plug in the pwr adaptor and boot w/o the battery.
- Pull you HDD and reinsert it and make sure its snug, try it again.
- Take the HDD out and try to boot w/o it.
- Pull the RAM out, reinsert one at a time and try again.
Let us know how it goes from there.