It's not a joke. It's a normal problem for 2007 HP Pavilion. The video chip on your motherboard is loose. If you google "bake motherboard", the first item is a youtube clip named "baking the motherboard-hp pavilion":
http://www.youtube.com/watch?v=jsmlALfEgPg
I did it for my HP Pavilion, but it lasted only 4 more months.