HP and AMD
Could it be that HP turned down free chips because they thought it would harm their image, and that it would impact the sales of other machines? If HP has lots of Intel chips on hand that they paid for, they might want to use those up before using the AMD Chips. If HP thought that by the time their supply was up of Intel chips the AMD chips would be obsolete, they might not choose to go with them.
Design considerations might have also played a part in this. If a machine is designed with a certain custom motherboard, the retooling of making a new motherboard or new case to work with the chip might be too expensive. The same with testing software with the new AMD chips to make sure that it works (HP diagnostics and other tools that work specifically with specific chipsets. The new chipsets might require new programming or the rewriting of the utilities on hand)
I think that Intel has shown predatory practices, but they are not at the same level as Microsoft. AMD realizes that they are slowly loosing the footing they had two years ago, and think that pursuing legal measures will either slow Intel down, or be a better investment then getting their new chips to market.