YLOD a term feared by any ps3 owner it pains me to watch this and as its is working again I would guess at a thermal paste problem if you are handy at crackin stuff open and having a go ten there are plenty of self help guides just get youself to maplin for some themal paste. That said a mate of mine had that problem with his and even though it was well out of warranty they replaced it with a refurbished model of same spec.