Can you give use more information to what's happening to your laptop? If it's not booting up or not displaying anything on the screen, please do try these troubleshooting steps.
- Start with a hard reboot, unplug it's AC adapter then press and hold the power button for 20 seconds then try booting it.
- If it doesn't work reseat the RAM, remove them all for couple of second then put them back in making sure everything is seated properly.
- Again if these doesn't work but you can hear the laptop on but with no display, connect an external monitor and see if it would display anything because if it does that means it's the built in display that is faulty.
- Next to try is if your AC adapter is still okay by trying another AC adapter that has the same voltage and see if it would work.
- If all these will not work then the problem is with the motherboard.
If it's just not booting up into Windows:
- Start again with a hard reboot.
- If it doesn't work do try and load in Safe Mode, repeatedly press on F8 while the laptop is booting up and wait until it loads Advanced Boot Options then select Safe Mode.
- Once in Safe Mode perform System Restore, put it back to an earlier date or time before the problem even happened.
- If it doesn't load Safe Mode that means your last option would be to reinstall Windows using a Factory Reset disc.