Hi,
Please do try these troubleshooting steps that may help.
- First is to do a hard reboot, remove the battery and unplug the AC adapter then press and hold the power button for 20 seconds then try booting it up again.
- If the lines are still on the screen without the mouse cursor, connect an external monitor and observe if you'll have the same problem.
- If the external monitor will be the same that could mean that the GPU is bad already.
- I would suggest taking it in for a repair if it's still under the factory warranty.