Tuesday produced one of 2026’s most remarkable divergences: the Dow Jones Industrial Average surged 659 points (+1.3%) while the Nasdaq 100 fell 1.74% and pushed toward technical correction territory. The villain was a single IPO — one that didn’t even happen in America. ChangXin Memory Technologies (CXMT), China’s state-backed DRAM manufacturer, surged 466% in its Shanghai STAR Market debut on Monday, raising $8.6–9.8 billion and becoming mainland China’s most valuable listed company at approximately $540 billion in market cap. The shockwave it sent through Western memory and semiconductor stocks on Tuesday ranks among the most coordinated sector selloffs in recent history.

The VanEck Semiconductor ETF (SMH) fell more than 3% for its fourth consecutive session in the red. The Nasdaq 100 entered correction territory — defined as a 10%+ decline from recent highs. And every name on today’s losers list shares a common thread: China’s memory ambitions just became impossible to ignore.

Top Stock Losers Today — July 28, 2026

📉 #1 — SanDisk (SNDK) | −11% to −14% | Close: ~$1,278 | Down 50%+ From Peak

This is the single most dramatic individual stock story in today’s market — and the central character in the broader semiconductor collapse.

Full Session Data:

SanDisk was the S&P 500’s top-performing stock of 2026 before this reversal. A 505% YTD gain through late June followed by a 50%+ collapse in a single month is the kind of mean-reversion event that defines market cycles.

Why It’s Being Hit Hardest:

The CXMT IPO is primarily a DRAM story — CXMT makes DRAM memory, not NAND flash. SanDisk specialises in NAND flash storage. So why is SanDisk the hardest-hit US memory stock?

The answer lies in YMTC — China’s NAND manufacturer. YMTC held approximately 11.8% of the global NAND market last year, broadly comparable to SanDisk’s share. Projections put YMTC at 14%+ by early 2027. The CXMT IPO’s explosive debut is the market’s clearest signal yet that Chinese semiconductor capital markets are now open for business at scale — and that YMTC’s path to a similarly explosive public listing could follow. Investors are pricing the YMTC threat into SanDisk now, not after the fact.

Adding fuel: reports emerged that Apple is testing CXMT chips — meaning China’s memory is reaching top-tier customers. If Apple qualifies CXMT as a supply source, the pricing implications for the entire memory supply chain are severe.

Technical Read: RSI at 35.95 and oversold stochastic readings suggest the selloff is stretched and a relief rebound is possible. However, the negative MACD confirms sellers remain in control below $1,308–$1,369 resistance. The $1,000 psychological level is now the market’s primary watch point.

📉 #2 — Western Digital (WDC) | −12.08% | Close: $437.77

Western Digital shares fell 12.08% to close at $437.77, extending what has become a punishing multi-week rout across storage and memory names.

Full Session Data:

Three Converging Negatives:

1. NAND flash oversupply fears: YMTC’s projected market share expansion to 14%+ by early 2027 directly threatens Western Digital’s NAND pricing power — which had been at historically elevated levels thanks to AI storage demand
2. “Circular financing” concerns: Nvidia was reported to be in talks to finance a $250 billion data center for OpenAI — raising concerns that AI infrastructure spending is being financed by the same companies supplying the chips, creating an artificial demand bubble
3. Pre-earnings risk reduction: With results due August 5, institutional investors are reducing size ahead of what could be a difficult guide given margin compression fears

Despite today’s selloff, WDC’s underlying fundamentals remain intact: HDD production is sold out through 2026, and Capital World Investors added 10.8 million shares (+1,017%) to their position in Q1 2026 — a signal that at least one sophisticated large investor is treating this as a buying opportunity.

📉 #3 — Micron Technology (MU) | −8%+ | 33% Below Its 2026 Peak

Micron fell more than 8% on Tuesday, extending a punishing decline that has now erased approximately one-third of the stock’s peak market capitalisation.

Key Data:

Micron’s fundamentals are objectively extraordinary: $41.46 billion in Q3 revenue (+345.7% YoY) and a $50 billion Q4 guide represents the most profitable stretch in the company’s history. But markets price the future, not the past — and the fear is that CXMT’s arrival as a fourth credible DRAM player at 8% market share (behind Samsung at 36%, SK Hynix at 29%, and Micron itself) begins to erode the pricing power that generated those record revenues.

The Roundhill Memory ETF (DRAM) fell more than 4%, reflecting the coordinated hit across the entire cohort. Samsung, SK Hynix, and Micron together represent 72% of that ETF’s net assets — making it one of the narrowest large-scale sector bets in the market.

📉 #4 — AMD (Advanced Micro Devices) | −8%+ | Caught in Chip Contagion

AMD fell more than 8% on Tuesday — not because of any AMD-specific negative catalyst, but because sector contagion is indiscriminate when the primary narrative is “Chinese semiconductor ambitions are accelerating.”

Why AMD Fell When It Shouldn’t Have:

AMD is not a memory company. It designs CPUs and GPUs for data centres, gaming, and AI workloads — it does not compete with CXMT or YMTC directly. But semiconductor sectors move as cohorts, and when the SMH (semiconductor ETF) falls 3%+, every name within it comes under selling pressure regardless of its individual competitive position.

The secondary narrative hurting AMD specifically: the broader “AI capex circular financing” concern. If Nvidia’s $250 billion OpenAI data center financing arrangement suggests AI infrastructure spending is being subsidised rather than driven by genuine end-demand, then every AI chip company faces a potential demand reckoning. AMD’s MI325X and MI355 GPU products are competing for precisely the data centre AI training and inference market that is under this scrutiny.

Technical: AMD needs to hold its 200-day moving average support to avoid triggering a deeper correction. Analysts broadly remain constructive — AMD has historically beaten EPS estimates in 63% of quarters tracked by EarningsWatcher — but technical selling on high volume can overwhelm fundamental support in the near term.

📉 #5 — SK Hynix (SKHY) | Sharply Lower | South Korea Triggered Circuit Breaker

SK Hynix’s US ADRs fell sharply for a second consecutive session as the CXMT IPO aftershock continued to reverberate. The Seoul session was even more severe — South Korea’s Kospi fell more than 10% and triggered a temporary trading halt (circuit breaker) as the domestic market registered the full impact of CXMT’s emergence as a major public company.

The Competitive Context:

CXMT holds approximately 8% of the global DRAM market — at a fraction of SK Hynix’s 29% share. But CXMT’s government backing, manufacturing scale-up momentum, and now access to public capital markets through its $8.6–9.8 billion IPO changes the competitive trajectory meaningfully. SK Hynix’s premium — specifically its leadership in HBM (High Bandwidth Memory) for Nvidia’s AI chips — is its key defence against Chinese competition. HBM requires specialised packaging technology that CXMT does not yet possess. But investors are asking: how long does that technology gap hold?

SK Hynix’s Q2 2026 earnings were due to be released on or after the US market close on Tuesday — making Tuesday a particularly volatile session as pre-earnings anxiety layered on top of the CXMT narrative.

📉 #6 — Seagate Technology (STX) | Sharply Lower | HDD Name Caught in Memory Rout

Seagate sold off sharply Tuesday alongside the broader memory and storage group. Seagate makes hard disk drives — not DRAM or NAND flash — but the sector-wide contagion from CXMT’s IPO extended to any storage technology company.

The Seagate Irony: Seagate’s most recent quarterly report topped estimates and its Q1 guidance – described as “blockbuster” by analysts at the time. Its HDD business is driven by data centre nearline storage demand (which grows with AI data volumes) — a business completely insulated from Chinese DRAM competition. Yet sector-level selling doesn’t discriminate by business model when the narrative is that “China is winning the memory war.”

📉 #7 — Core Scientific (CORI) | −9% | AI Bitcoin Miner Faces Double Headwind

Core Scientific — which has mostly pivoted away from pure Bitcoin mining toward AI data centre hosting — fell 9% on Tuesday.

Why It’s Falling Despite the Pivot:

Core Scientific’s AI data centre strategy is primarily built on hosting Nvidia GPU clusters for AI workloads — renting rack space, power, and cooling infrastructure to AI companies that need GPU compute. That business model is:

1. Directly exposed to the Nvidia “circular financing” concern: If the $250B OpenAI data center is being financed by the same supply chain (Nvidia → OpenAI → Nvidia chip purchases), the concern is that GPU compute demand is being artificially inflated
2. Exposed to semiconductor sector sentiment: When Nvidia falls 5% (as it did Monday) and the SMH falls 3%+, the companies whose business case is built on Nvidia demand take collateral damage

Core Scientific’s Q2 2026 Earnings Call highlighted “strategic partnerships and robust” results — suggesting the business is operationally sound. Tuesday’s move is narrative-driven, not fundamental.

📉 #8 — Cipher Mining | −8% | AI Bitcoin Miner Hit by Semiconductor Selloff

Cipher Mining led the Bitcoin/AI miner group lower with an 8% decline. Cipher is positioned at the intersection of Bitcoin mining and AI GPU infrastructure — a positioning that generates premium valuation in risk-on markets but acute vulnerability when semiconductor sentiment deteriorates.

The specific concern: Cipher Mining’s infrastructure economics have direct ties to the cost and availability of high-end computing hardware. If Chinese memory competition drives down the cost of AI compute (a long-term positive for AI users but a near-term margin compressor for data center operators), Cipher’s GPU hosting revenue rates come under pressure.

📉 #9 — Hut 8 | −6% | Crypto Miner Dragged by AI Chip Fears

Hut 8 fell 6% as semiconductor weakness extended into the AI-exposed bitcoin mining category. Hut 8 has been aggressively investing in GPU compute infrastructure for AI hosting alongside its traditional Bitcoin mining — making it a dual-exposure name that falls when either Bitcoin sentiment weakens or AI infrastructure sentiment deteriorates. On Tuesday, both headwinds hit simultaneously.

📉 #10 — Rambus (RMBS) | −4%+ | The Cruel Paradox of Beating Estimates in a Selloff

Rambus fell more than 4% on Tuesday — despite beating Q2 estimates on both revenue and earnings per share. Rambus reported adjusted EPS of $0.77 against the LSEG consensus of $0.72 (+6.9% beat), with revenues of $207 million versus the $198 million estimate (+4.5% beat). Both numbers were solid. The market’s response was to sell the stock 4%.

Why a Beat Doesn’t Matter When the Sector Is Collapsing:

Rambus makes memory interface chips — the silicon that controls how DRAM memory interfaces with processors. It is therefore a direct exposure to the DRAM supply chain narrative. When investors believe DRAM pricing will decline due to Chinese competition, Rambus’s royalties and chip revenues are to follow — regardless of the current quarter’s results.

This is the cruelest reality of sector-level selloffs: even companies executing flawlessly take a hit if they sit in the wrong category at the wrong moment. Rambus’s 4% decline on a beat is a textbook example.

The CXMT Factor: The Story Behind Today’s Losers

Every name on today’s list traces its decline to one event — and understanding that event fully is the difference between a panic seller and an informed investor.

CXMT’s IPO in Full:

The coordinated selloff spans NAND and DRAM names alike, signaling a sector-wide reaction rather than a single-stock story. The Roundhill Memory ETF (DRAM) — which tracks the entire cohort — fell more than 4%, erasing months of gains in a single session.

The Market’s Key Question: Is CXMT a genuine competitive threat to Western memory incumbents, or is the market overreacting to a Chinese IPO in a sector that still requires technology CXMT doesn’t yet possess? CXMT is the world’s fourth-largest DRAM maker at just 8% share — far behind Samsung, SK Hynix, and Micron. Its HBM manufacturing capability is years behind SK Hynix’s. The Apple chip testing report remains unconfirmed.

But the market isn’t trading today’s CXMT. It’s pricing 2027’s CXMT — with government backing, fresh public capital, and a semiconductor industry that has watched China’s solar and EV industries go from zero to dominant in less than a decade.

Tuesday’s Losers — At a Glance

Also notable: Terawulf (WULF) −4%, MARA Holdings −3%, Riot Platforms (RIOT) −5%, Hilton Worldwide (HLT) −2.7% (Q3 guidance miss), Universal Health Services (UHS) −3% (full-year guidance cut)

Follow TNN for daily stock market news and financial news today.

Disclaimer: This publication is entirely for informational and journalistic purposes and does not constitute formal financial, investment, or legal advice. All market investments carry inherent risks of capital loss. Session prices and percentage declines cited reflect intraday and closing data as of July 28, 2026, sourced from CNBC, Benzinga, FX Leaders, 247 Wall St., and Yahoo Finance. Analyst price targets and competitive projections (including YMTC market share estimates) are third-party figures and do not guarantee future outcomes. Always complete independent due diligence prior to executing equity trades.

About The Author

Kasia Davis

See author's posts