We've been hearing about a so-called post-PC era for several years, but now it seems we finally have some hard evidence. As of this year, PCs are no longer the world's greatest memory chip consumers.

According to a press release from research firm IHS, formerly known as iSuppli, the second quarter of 2012 marked the first time in a generation that PCs did not consume the vast majority of commodity memory chips known as DRAM.

During the second quarter, PCs accounted for the consumption of roughly 49 percent of DRAM produced worldwide, down from 50.2 percent in the first quarter of 2012. The share of these DRAM chips going into PCs, both desktop and notebooks, had been hovering at or near 55 percent since early 2008, noted IHS.

PCs have consumed the majority of memory chips since the 1980s, although IHS could not determine exactly when the first PCs started showing up in significant numbers in homes and businesses worldwide.

Now, the majority of those memory chips seem to be going into tablets and smartphones. IHS estimates that phones consumed more than 13 percent of memory chips manufactured, and it expects that figure to surge to nearly 20 percent by the end of 2012. Tablets, including Apple's market-leading iPad, accounted for just 2.7 percent of the world's memory chip supply. Meanwhile, the remaining 35 percent which IHS classified as "other" includes servers, professional workstations, and presumably specialized applications such as embedded systems and supercomputers.

Based on their whopping growth rates, IHS expects phones and tablets combined to consume roughly 27 percent of the world's memory supply by 2013, while PCs will consume less than 43 percent by that time. In the firm's estimation, that decline will be irreversible.

When it comes to PC makers, particularly HP, Dell, and Lenovo, this undeniable shift marks the beginning of an overall decline in the importance of PCs as consumers in the chip supply chain. Large memory chip makers such as Samsung, Micron and Hynix will increasingly focus on the phone and tablet business, and gradually focus less on the needs of PC makers.

"PCs are no longer generating the kind of growth and overwhelming market size that can singlehandedly drive demand, pricing and technology trends in some of the major technology businesses," explained IHS analyst Clifford Leimbach.