Although external USB 2.0 enclosures are affordable the lack of internal hard disk has implicated a problem for users with perhaps little knowledge of the software required to enable the external disk functionality.
Not only did Sony roll out the PS2 online adapter in late 2002 to compete with Microsoft, several online launch games were first party titles such as SOCOM US Navy SEALS in order to show that Sony was supporting this feature actively.
Only a few million users had obtained consoles by the end of 2000 due to manufacturing delays.
It was not until late 2001 that the Microsoft Xbox became the second console with (non-standard) USB and DVD support.
The PS2 also supports PS1 memory cards (for PS1 game saves only) and controllers (the PS2's Dual Shock 2 controller is essentially a slightly upgraded PS1 Dual Shock).
The PS2 hardware can read both compact discs and DVDs.
It also has a different lens and some compatibility issues documented by Sony for earlier PS2 games.
In September of that year, in time for the launch of Grand Theft Auto: San Andreas (the best-selling game during the 2004 Holiday season), Sony revealed a new, smaller PS2 (see Hardware revisions).
In preparation for the launch of a new, slimmer PlayStation 2 model (SCPH-70000), Sony had stopped making the older PS2 model (SCPH-5000x) sometime during the summer of 2004 to let the distribution channel empty out stock of the units.
PS2's opening day console sales eclipsed the previous record of 225,000 made by the Sega Dreamcast in 1999.
There are also some disputes on the numbering for this PS2 version, since there are actually two sub-versions of the SCPH-70000.
To this day, the PS2 holds the record for the most consoles sold in a single day as well as the record for most consoles sold in launch day in America.
