If it's not too old it's worth contacting HP.
I had the same problem with an HP dv5.
I contacted HP (laptop bought through Dixons/Currys who didn't want to know) pointing out that while the machine was more than a year old the problem was a well known and publicised manufacturing fault.
Also pointed out the EU regulations say the warranty period for such goods within the eu is 2yrs.
I specified that an acceptable resolution would be either a permanent repair or a replacement with a reliable similar machine.
HP accepted this and took the laptop back.
They replaced the motherboard and processor and fitted "upgraded" cooling.
It's worked like a dream since then.
I found that being polite but firm seemed to work ... first level support did not want to play but eventually they passed it upwards .. once they decided to accept responsibility the service was impressive and quick.
