Ok. Thanks guys for the leads. Yes it was the nVidia chipset thing. I had heard of this before but didnt realise it affected so many of the HP models (thought it was just the DV6000's) turns out its the 2000 6000 and 9000 series - HP really sucked on that one.
So then I had a look into the repairs.
MOBOs for these things are available on ebay for about $150 , but they are second hand from China and I wasnt keen to put one of these into the customer's machine. I advised him of this option but also advised that I thought it wasnt a great idea as no guarantee of the issue not occurring again.
Then I contacted HP parts supplier who quoted me $600 for a new motherboard. Needless to say, I didnt even offer the custiomer this option as he was balking at the $280 I would have charged him for the 2nd hand board so there was no way he was going to shell out $700+ for the new item, plus too much to spend on that machine for a repair anyway.
I had a look at the repair motherboard options. The heat gun thing seems to have yielded unreliable results, and I wasnt keen to try a repair that was just a temporary measure.
I finally landed on the IR heat station repair, and that looked like the best bet as its precise in terms of heat generation and local to the specific part that needs to be heated - rather than hot air which seems to go all over the place. I then located someone here (adelaide, australia) who has the gear and has done the repair to the dodgy HP models. He charges $280 for the repair (nbot a bad mark up I thought given no parts involved) but at least the repair is done properly. I then put the customer in touch with the repairer and he is going to pursue this route.
Thanks to everyone for your replies. I wouldnt have had a clue without the help. As I progress with laptop repairs I am finding that I have a hell of a lot to learn and I am so thankful for this forum as a place to go and get decent information.
