Apple captured 3.7 percent of the U.S. personal computer market in the second quarter of 2004, shipping 495,000 Macs to Americans, according to research firm IDC. Apple’s year over year growth was 9.3 percent, although the company’s market share this time last year stood at 3.8 percent. Dell led all manufacturers with 32.9 percent market share. It was followed by HP (19.3 percent), Gateway (5.6 percent), IBM (5.6 percent) and Apple.