China's newest memory champion – ChangXin Memory Technologies (CXMT) – is finally public on the Shanghai market.

Investors immediately assumed that meant more trouble for Micron Technology Inc.

(NASDAQ:MU) and SanDisk Corp.

(NASDAQ:SNDK), two of the best-performing names in the S&P 500 this year.

Following CXMT's eye-popping 466% debut, Wall Street dumped virtually every memory stock in sight.