[CITIC Securities: It is recommended to pay attention to the investment opportunities of companies in the HDD, DRAM, and NAND tracks] On October 16, CITIC Securities reported that the recent global memory chip stock price fluctuations have intensified, and their performance has been significantly weaker than other sectors since October. In addition to the disturbance of macro factors (increased crude oil price fluctuations, inflation and interest rate expectations have resurfaced), the industry has also become more concerned about the progress of Changxin Technology’s 4F² technology. The main reason is that the market is worried that China's local wafer fabs will form an effective technological breakthrough in the high-margin server DDR5 market, and the narrative logic of overseas giants maintaining ultra-high bargaining power through monopolizing production capacity will be shaken. From the perspective of industry progress, the current DRAM technology is still dominated by 6F² unit structure. The implementation of 4F² technology depends on the progress of Samsung Electronics and Changxin Technology. At present, 4F² technology is still in the early verification stage. It is still necessary to observe the company's yield, output, gross profit margin, downstream customer certification and other indicators in this field. It will have a relatively small impact on the short- and medium-term storage industry. It is recommended to pay attention to the investment opportunities of companies in the HDD, DRAM, and NAND tracks.