The difference is that series 4000 APU is a serious contender for Intel in price/performance/power consumption where 3000 series was still lacking in comparison to Intel offerings, and 4000 series was aiming especially at the high end/higher margins laptops, being 8 core native. And you don't contend on a low margin market like the one covered by Intel with 2 /4core APUs with a 8 core native part on a more expensive process. AMD has not the same resources as Intel, and thus they have priorities, and of course their priorities are where the higher the margins are. In the meanwhile, if you want an AMD APU with low core count, you can go for the older 3000 series which still offers more than good competition with even priced Intel parts.