Is there any proof that hard drive manufactures actually switched? It's always just repeated as truth. I remember megabytes being all over the place in the days of floppy disks, 1000 * 1000 or 1000 * 1024 or 1024 * 1024. Hardware engineers have always been more likely to use 10^9 (ie megabits) where software developers have always been more likely to use megabytes.