Apple has been testing memory chips from China's ChangXin Memory Technologies (CXMT) across product lines including iPhones and MacBooks, according to a report today from The Wall Street Journal ($). Laptop makers HP and Acer have already started using memory chips from CXMT in devices sold outside the U.S. Meanwhile, Apple has held early talks with CXMT about supplying components for devices sold in China, and the company is hoping for a sign-off from the White House before going further.