I think my ps3 is broken, a little hlp ne1?

So my ps3 is broken, its one of those fat ps3's , 40 gig.. i think. My Ps3 starts properly but when i stay on it for about 3 minutes or if i play a game (a Cd and or demo) my ps3 freezes.. and shuts down and when it shuts down, the red light starts blinking.