Why South Korean Memory Chip Stocks Crashed 10%: CXMT IPO, Nvidia Circular Financing, and a Bear Market

South Korean memory chip stocks suffered one of their worst single-day routs on Tuesday, July 28, 2026. The benchmark KOSPI plunged as much as 10%, triggering both a temporary trading sidecar and a full circuit breaker . But this was no isolated panic — it was the culmination of three distinct shocks hitting an already fragile market.

The Selloff in Numbers

The scale of the damage was extraordinary. The KOSPI dropped to its lowest level since April . Samsung Electronics fell as much as 9.5%, while SK Hynix dropped up to 12.6% during the session . Other AI-linked Korean names were swept up in the selling: Samsung SDI fell over 7%, LG Innotek slid nearly 14%, and Japan's Kioxia plunged more than 15% .

1. CXMT's Explosive STAR Market Debut (July 27)

The trigger arrived the day before. Chinese DRAM maker ChangXin Memory Technologies (CXMT) raised 57.92 billion yuan ($8.6 billion) in Asia's biggest IPO of the year . On its first trading day, the stock surged 531% in the morning session and closed up roughly 466% at 49 yuan, versus an IPO price of 8.66 yuan . The listing cemented CXMT as China's first viable domestic DRAM champion, filling a global supply gap and positioning itself as a direct competitor to Samsung and SK Hynix .

For South Korean investors, the message was unmistakable: China is closing the gap in memory chips far faster than expected. The CXMT listing was interpreted as a direct threat to the market share and pricing power of the two Korean incumbents .

Adding to the anxiety, CXMT's debut raised concerns about a potential liquidity squeeze in Chinese equities, as investors raised funds to get a piece of the blockbuster IPO .

2. Nvidia's $750 Billion 'Circular Financing' Concerns

On Monday, July 27, Bloomberg reported that Nvidia was working on a fresh round of AI infrastructure deals potentially worth over $750 billion . The package included a $500 billion AI initiative with SK Group (the parent of SK Hynix), a guarantee of up to $250 billion to help OpenAI lease computing from a U.S. data center project, and discussions about financing $350 billion of OpenAI's Nvidia chip purchases .

Skeptics immediately labeled these deals "circular financing" — the concern that Nvidia is effectively lending or investing money to customers who then use the funds to buy Nvidia chips, artificially inflating demand and valuations . Critics argue that when a chip supplier funds its own customers' purchases, the resulting revenue growth is not purely organic .

This narrative dealt a direct blow to AI-driven memory demand expectations. SK Hynix, as Nvidia's key supplier of high-bandwidth memory (HBM) chips for AI servers, was hit hardest .

3. A Market Already in Bear Territory

The Tuesday selloff landed on a market that was already deeply wounded. The Philadelphia Semiconductor Index (SOX) had entered a technical bear market on July 17, falling more than 20% from its late-June record high . This came after a stunning 105% AI-driven rally from March to June that had fully unwound .

According to Bloomberg data, roughly $3.3 trillion in global chip-stock market value had been erased since June 22 . The KOSPI itself had already slid 23% from a recent high in June by July 8, dragging it into its own bear market .

This fragile backdrop meant any new negative catalyst would trigger outsized losses, which is exactly what happened on Tuesday.

4. The Paradox of the $500 Billion Nvidia-SK Partnership

The same Bloomberg report that detailed the circular financing concerns also highlighted a major AI initiative between Nvidia and SK Group . But rather than reassuring the market, the sheer scale of the partnership fed the circular financing narrative. Investors feared that the partnership essentially meant Nvidia financing its own demand through SK Group, making the order book look less organic .

In other words, what might have been read as "good news" — a massive partnership securing AI chip demand — paradoxically worsened sentiment because it looked like more vendor financing rather than genuine end-user demand.

Summary: A Cascade, Not a Single Event

The Tuesday selloff was not caused by a single headline. It was a cascade:

• CXMT's blockbuster debut freshly terrified investors about Chinese DRAM competition threatening Samsung and SK Hynix's core business.
• The circular financing story cast doubt on the authenticity of AI chip demand, directly undermining the thesis that had driven memory stocks to record highs.
• The bear-market backdrop meant that any negative catalyst would trigger amplified selling, as momentum traders and leveraged positions unwound.

The huge Nvidia-SK partnership paradoxically worsened sentiment because it looked like more circular financing rather than organic demand. The result was one of the worst days for South Korean chip stocks in recent memory.