Comment Motorola owns the patent (Score 1) 30
A colleague of mine working for Motorola patented encrypted memory sometime in the 2006-2010 timeframe. Maybe Motorola figured out that AMD was violating their patent and negotiated royalties privately with AMD. I don't know; I don't work at Motorola, but if AMD had to suddenly start paying royalties, it makes sense that they'd remove the feature from lower end, lower margin processors.