Samsung Is Closing the HBM Gap — And China Just Entered the Ring
SK Hynix still leads HBM with 50% share, but Samsung surged from 21% to 33% in one quarter as the market pivots to next-gen chips. Meanwhile, China's CXMT has started HBM3E production, adding a new variable to an already fierce memory chip race.
The HBM market is no longer a two-horse race.
SK Hynix still commands the crown with 50% of global HBM sales in the second quarter, but the gap to Samsung Electronics has collapsed dramatically. Samsung’s share jumped from 21% to 33% in a single quarter, narrowing the distance between the two Korean giants from 37 percentage points to just 17. Micron sits at 18%, and now China’s CXMT has crossed the finish line into volume production — however small.
What makes this moment significant is not any single data point but the convergence of three forces: the generational handoff from HBM3E to HBM4, Samsung’s aggressive catch-up strategy, and a Chinese entrant that changes the long-term calculus.
Samsung’s bet on the next generation
Most HBM revenue today still flows from HBM3E chips. But that is shifting fast. NVIDIA’s next-generation AI accelerator, the Vera Rubin, ships with HBM4, pulling the market center of gravity upward. Samsung knows it cannot win by chasing on old technology, so it is betting the farm on the transition.
The company plans to triple its HBM4 revenue in the third quarter compared to the second. That is a steep ramp, and execution risk is real. But the direction is clear: Samsung is treating the generational shift as its window.
Several Wall Street and Korean research firms agree the shift could flip the standings. UBS projects Samsung will capture 41% of the HBM4 market next year, edging past SK Hynix’s estimated 39%. KB Securities is even more bullish, forecasting 44% for Samsung alongside a doubling of average selling prices. Together, those projections imply Samsung’s total HBM shipments will surge 137% year over year next year.
SK Hynix is not standing still. It has stabilized HBM4 yields and is beginning to raise production. Both companies are also racing on HBM4E, the step beyond HBM4. The generation that wins next year may be decided this quarter.
Micron is doubling down, too
Micron’s position as the third player matters more than its current share suggests. The company is expanding HBM production capacity to roughly 100,000 wafers per month by year-end, up from 40,000 to 50,000 last year. That is a doubling. HBM4 12-layer wafers, which made up only 20% to 30% of its mix at the start of the year, are expected to reach 50% by December.
Micron passed $1 billion in cumulative HBM4 shipment revenue after starting volume production in the second quarter. The company is betting that demand from NVIDIA, AMD, and its own custom-chip customers will absorb the expanded capacity. If it is right, Micron becomes a meaningful swing factor in the HBM4 market — not just a distant third.
China’s entry changes the math, eventually
CXMT’s entry is the story most English-language coverage underplays. The Chinese DRAM maker began small-volume HBM3E production this year, after originally targeting the older HBM3 standard. It plans full-scale manufacturing by 2027 and intends to supply Chinese fabless designers. Alibaba’s semiconductor subsidiary T-head and AI chipmaker Cambricon are already evaluating CXMT’s HBM3E for their own processors.
On paper, a three-year gap sounds manageable. Samsung and SK Hynix started HBM3E volume production in 2024; CXMT is just now shipping small volumes. But three years in semiconductor time is a long time, and the gap is already showing. Industry assessments say CXMT’s HBM trails the Korean products in both speed and reliability — critical weaknesses when you are powering data-center AI workloads.
Still, the direction matters. China has invested tens of billions to build a domestic supply chain that can feed its AI ambitions without relying on Korean memory. CXMT’s move from HBM3 to HBM3E in a single step signals that the追赶 is accelerating. By the time CXMT reaches HBM4 volume, the quality gap may have narrowed enough for cost-sensitive buyers to take the risk.
Who wins, who loses
In the near term, Samsung wins the most. Its HBM4 ramp, if executed, closes the market-share gap with SK Hynix and repositions the company as a credible alternative to NVIDIA’s primary memory supplier. Buyers diversify their supply chains away from a single Korean vendor — a trend already underway — and Samsung captures share.
SK Hynix loses ground but not the lead. Its 50% share reflects deep relationships with NVIDIA and other top AI chip designers that took years to build. Those relationships will not evaporate overnight. But the 8-percentage-point drop in one quarter is a warning sign that the moat is thinner than it looked.
Micron gains capacity and potentially market relevance if it can match Korean yield rates at scale. CXMT gains a foothold in a domestic supply chain that may matter enormously by 2028 — and possibly earlier for less demanding applications.
Chinese AI chip designers gain an option they did not have before. Even a lower-spec memory chip from a trusted domestic supplier reduces geopolitical risk, which is a form of value in itself.
What happens next
The HBM market will likely consolidate around three or four players by 2028, not two. SK Hynix and Samsung will compete head-to-head on HBM4 and HBM4E. Micron will press for share with expanded capacity. CXMT will aim for the Chinese market first, then test whether quality improvements open doors elsewhere.
The most important variable is yield. Whoever stabilizes HBM4E production first gains a structural advantage, because the next jump in AI performance depends on it. The second variable is pricing. If Samsung’s projections about ASP doubling hold, margins expand for everyone — but the winner takes more than its share of the pie.
For the moment, the HBM war is no longer about who makes the best memory chip. It is about who can ship the most at the right price while China builds its own factory. The AI boom runs on HBM. Whoever controls that pipeline controls a piece of the future.
Sources: Counterpoint Research, UBS, KB Securities, industry reports.