HP Pavilion Dv6 Laptop Help?

I bought a HP Pavilion Dv6 A little over a year ago. and i never had any problems with it till recently. First it started over heating. So i went and bought a cooling pad. Problem Solved... Then My computer cord quit, so i went a bought a new power cord. Problem Solved.. Then a couple months after that everytime i went to watch a video on my laptop with it plugged up, it would crash.(screen turn black, volume turn off, have to manually turn off the computer to fix it). Videos would play perfectly if wasnt plugged up. Did multiple virus scans. Malware scans, Ect.. Cleaned disks. Cleaned out computer. Nothing changed. It still crashed everytime watching a video. After it would crash it would take hours before i could finally get it turned back on. So when i finally got my computer turned back on. I decided to do a system restore since i thought that, that was logical thing to do. When in system restore. Computer crashed multiple times. i Had to keep turning back on the computer which i knew was going to mess with the process. But everytime i turned the computer back on, it continued from where it left off. Well when i got to where it was going to install windows 7. an error popped up saying that i needed to restart the installing process. So i restarted this multiple times. Finally i gave up and left the laptop turned off.. I went to turn the laptop back on, and it turns on except the screen stays black.

I dont know if my laptop is fried, or what i can do to fix this. But if anybody knows anything it would be highly appreciated. Thanks =)

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