computer shuts down

I have to be quick before I lose the connection again My PC shuts down and restarts after 10 minutes on Yahoo. I have run symantec corp version, ad aware, spy bot, kasperski, AVG, clean up and windows defender and they all find nothing. Whats happening? I have been tp several other forums and seen several people complaining about the same thing..is it a new thing going around…something with MS media player 11 Can some please help me again Thanks jd

Hi,
Sorry to hear of the problem with your computer shutting down.
Have you had a look here?
http://askbobrankin.com/computer_restarts_itself.html
Regards
paws

No I havent but I will. The machine seems to be just fine during normal operation and during games laoded into the PC.and will run "forever". But 10 min after being in the net or downloading anything from a pic to a doc file, it shuts down and restarts…I will check the recommended suggestions and be back Thank you JD