patriot 2450 (model number n34as6)

[jonnyboy]

hi all, i have a patriot n34as6, this unit runs for a short while but seems to have a heat related problem as it keeps just shutting down, when it has shut down it runs again for seconds before shutting down again. also sometimes the the inverter drops out and screen goes dark. does anyone have any ideas on this?? done many laptops in the past but never come across this fault before. thanks guys. Jon.