HP is notorious for overheating issues. They have really shady business practices to save themselves money. It's difficult for a consumer standing around at Best Buy to know that the computer is going to overheat. HP will often put the GPU and CPU on one heat sink, and pipe all the heat from the CPU straight over the GPU on the way to the one fan that is supposed to cool it.
I've had to have my motherboard replaced on my current Pavilion 3 times. Each time, HP lied to me about the manufacturing, lied to me about my warranty, and ripped me off on the repair. One time, they stole one of my hard drives during the repair. Each time, they refused to service my machine and hung up on me. I had to call back over and over and threaten to sue before I could get help.
Do yourself a favor and don't buy HP products ever again. They are a very shady business and do not care about the consumer at all. They make shiny looking cases and that's it.
Acer and Asus are much better manufacturers, and they take cooling their systems and overall construction much more seriously.
In the meantime, I bought a cooling pad for $40 at walmart that has worked extremely well for me, and I never separate it from my laptop ever. It's helped with the majority of my heat problems. I can't WAIT to finally retire this machine and get a new Asus G73!