SanDisk (NASDAQ:SNDK<\/a>) stock has tumbled 45% over the past month, leaving memory and storage investors reeling. The selloff has rippled through the sector, with Micron (NASDAQ:MU<\/a>) stock down 26.82%, SK Hynix’s (NASDAQ:SKHY<\/a>) U.S. ADR shares falling 12.98%, and Western Digital (NASDAQ:WDC<\/a>) stock declining 12.78% over the same period. <\/p>\n The broader memory theme hasn’t offered much shelter either. The Roundhill Memory ETF (CBOE:DRAM<\/a>) is down 30.03% over the past month, demonstrating that diversification across the memory and storage ecosystem hasn’t shielded investors from the recent downturn. That’s left many wondering whether it’s time to cut losses on SanDisk and rotate into Micron or SK Hynix, or perhaps stick with the diversified ETF approach. <\/p>\n The SanDisk Selloff: What Went Wrong? <\/p>\n SanDisk stock’s\u00a0dramatic decline reflects a broader reassessment of memory and storage valuations after a blistering run earlier in the year. SNDK\u00a0shares had surged more than 100% in the two months leading up to late June, driven by enthusiasm around AI-driven demand for NAND flash memory and data storage solutions. However, that enthusiasm left little room for disappointment when sentiment toward high-flying semiconductor stocks reversed. <\/p>\n SanDisk’s trailing 12-month (TTM) P\/E ratio sits at 42.77x, which is elevated though not outrageous by growth-stock standards. The concern among some analysts is that SanDisk’s valuation had become stretched relative to near-term earnings visibility, especially as investors began questioning whether AI-driven memory demand would sustain the torrid pace seen in early 2026. <\/p>\n Act now: the analyst who called NVIDIA in 2010 just named his top 10 AI stocks \u2014 and Micron Technology didn’t make the cut. Grab the names FREE today<\/a>. <\/p>\n Micron and SK Hynix: The Alternatives <\/p>\n Micron stock has also taken a hit, but the decline of 26.82% is less severe than SanDisk’s 45% drop. Micron’s TTM P\/E ratio of 44.26x is slightly higher than SanDisk’s, but Micron’s positioning as a U.S.-based DRAM and NAND producer with strong ties to domestic AI infrastructure spending has kept some investors supportive. Micron is also making strides in high-bandwidth memory (HBM), though it still trails SK Hynix’s market share in that critical AI-chip segment. <\/p>\n Story Continues <\/p>\n SK Hynix stock has proven to be more resilient, as it’s down just 12.98% over the past month. SK Hynix’s dominant position in HBM and its close relationship with NVIDIA (NASDAQ:NVDA<\/a>) have been key factors supporting the stock. While a TTM P\/E ratio isn’t yet available for SK Hynix U.S. ADR shares, the company’s superior gross margins and operating leverage in the AI memory market have made it a favorite among analysts who see continued upside as AI data center buildouts accelerate. <\/p>\n The Case for the DRAM ETF <\/p>\n The Roundhill Memory ETF offers diversified exposure to the memory and storage sector, holding positions in SanDisk, Micron, SK Hynix, Western Digital, and other global players. The ETF’s TTM P\/E ratio of 23.27x is notably lower than the individual stock valuations, reflecting the diversification benefit and the inclusion of some lower-multiple names in the portfolio. <\/p>\n The Roundhill Memory ETF has fallen approximately 30% from its all-time high, marking a move into technical bear market territory. Despite the decline, the fund held roughly $25 billion in assets under management as of late July, suggesting that investors remain committed to the long-term memory thesis even as short-term volatility persists. For investors uncertain about picking individual winners, the ETF’s diversified approach could provide a smoother path through the sector’s ups and downs. <\/p>\n What Can Investors Do Now? <\/p>\n SanDisk stock’s steep decline raises the question of whether the worst is over or whether further downside awaits. SanDisk could recover if AI-driven storage demand remains robust and the company executes well on its product roadmap. However, SanDisk faces competition from Micron, SK Hynix, and Western Digital, any of which could capture market share if SanDisk’s stumbles. <\/p>\n Micron\u00a0and SK Hynix\u00a0each offer compelling narratives, with Micron’s\u00a0U.S. positioning and SK Hynix’s HBM leadership representing different paths to growth. The Roundhill Memory ETF\u00a0remains an option for investors who prefer not to make that choice, though the ETF’s 30% decline shows that diversification hasn’t eliminated risk. <\/p>\n Investors should consider keeping their position sizes modest if they choose to add to or initiate positions in SanDisk, Micron, SK Hynix, or the Roundhill Memory ETF at their current levels. The memory sector’s long-term prospects tied to AI infrastructure remain intact, but the recent volatility underscores the importance of prudent risk management. Furthermore, market watchers may want to look for signs of stabilization in memory pricing and demand trends before committing significant capital. <\/p>\n Act now: the analyst who called NVIDIA in 2010 just named his top 10 AI stocks \u2014 and Micron Technology didn’t make the cut. Grab the names FREE today<\/a>. <\/p>\n<\/a> Thinkstock <\/p>\n