I used to run windows 7.I dont why windows 7 shut down without notice.Especially when I watch HD videos.I reinstalled windows 7 but nothing much changed.

So this is how I started to use Linux.First I tried to install Nvidia drivers on Mint 14 but I couldnt.I did actually but I couldnt activate it.Eventually I had to reinstall Mint.Now it works well without Nvidia drivers.

and then I heard that some distros had Nvidia drivers installed already.And I tried out PcLinuxOS ( even LXDE), Sabayon, Mageia.
they all installed nvidia drivers automatically.But interestengly my laptop shut down again !

Now I am able to watch HD videos on Mint (or on other distros).But I can't watch them on windows 7,PcLinuxOS,Sabayon or Mageia.I have read many times, new nvidia drivers works perfectly and even make other resources of laptop use less ..But there is opposite situation in my case..

So what could the reason of my problem be ?

could a virus which works on BIOS be the reason?

Thanks

That sounds like a hardware problem with your graphics card. The nVIDIA drivers will most likely mean that hardware acceleration is used so the card is worked more, which is when it fails.
If you're lucky this could just be due to overheating -- have you opened nvidia-settings and checked the temperature when doing any of the things which crash your machine? Have you ensured that the fan on the graphics card, if any, is running and that the heatsink is free of dust?