This isn't going to be a long read. The simple answer, and this is a guess, is that HP sees three things.
In all honesty, I used to love HP, but not for the reasons you might think. Their enterprise and server gear has long been solid, including their desktop and laptop products. I have much experience with many years of such equipment. That changed for me a few years ago when I purchased a brand new HP ProBook 4540s. Aside from the display being of lower resolution than I wanted, the machine was a 15.6" mid-range powerhouse. It has a 2.5GHz 3rd-gen Core i5, 8GBs of RAM, 750GB drive, all of the expected widgets for connectivity, and hybrid graphics featuring Intel HD 4000 for mundane stuff and an AMD Radeon HD 7650M with 1GB of RAM. That last item would be perfect for my gaming needs, which aren't cutting edge, but can tax integrated systems. I thought I'd found my soulmate, and at $600, a thrifty value, too.