Hello!
Some of the newer HP lappies have issues with inadequate heat sinking on the graphics chip. As a result, the chip gets so hot that the solder connections on the chip itself start to melt. As a result, the soldered connections on the chip then have to be reflowed.
Reflowing the chip requires a considerable investment in a reflow workstation to get it done right, and a heck of a lot of masking with Kapton tape - not to mention stripping the lappy to its guts and removing the motherboard...
73 DE N4RPS
Rob