	At the time of its release, many users noticed that performance suffered as a result of upgrading from System 6 to System 7, though newer hardware soon made up for the speed difference. Another problem was System 7's large "memory footprint": System 6 could boot the system from a single 800k floppy disk and took up about of RAM, whereas System 7 used well over a megabyte. It was some time before the average Mac shipped with enough RAM built in for System 7 to be truly comfortable. System 7 was the first system release that could no longer be usefully run on floppy-only systems. Although most Macintosh models sold at the time included a hard disk as standard equipment, owners of older models were required to upgrade by buying either a new Mac or external SCSI hard disk drive if they wished to run System 7.