Does HP use the chip you want in similar laptops? You may need a BIOS upgrade to support the new CPU, and the ONLY source of such an update would be HP. If HP doesn't use that chip it is unlikely that they would provide an updated BIOS. If the new CPU requires more power, that could also lead to issues.
In short, I don't have any experience in upgrading laptop CPUs. It's always seemed to be more trouble than it was worth.