Due to its thinner profile, it does not contain the 3.5" expansion bay, and therefore does not support the internal hard disk drive but due to the presence of USB 2.0 ports an external USB Hard disk can still be used, and now uses an external power supply, like the Gamecube.
V5 introduces minor internal changes and the only difference between V6 (sometimes called V5.1) and V5 is the orientation of the Power/Reset switch board connector, which was reversed to prevent the use of no-solder modchips.
The PS2 hardware can read both compact discs and DVDs.
However, the release of several blockbuster games during the 2001 holiday season pushed the PS2 far in front even as the Xbox and GameCube made their impressive debuts.
During one week in November, sales in the entire country of Britain totalled 6,000 units - compared to 70,000 a few weeks prior.
Many analysts predicted a close 3-way matchup between the PS2 and its soon-to-be-released competitors Microsoft Xbox and Nintendo GameCube, noting that the PS2's graphics were inferior but that it had the advantage of a head start, and had a wide assortment of games of every genre (Xbox's strength was in its hardware; GameCube was the cheapest of the 3 consoles).
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.
Although Sony placed little emphasis on online gaming during its first year, all that changed because of the launch of the online-capable Xbox.
Developers also complained that it was difficult to develop for the system, with little in the way of reference material from Sony for its exotic architecture.
In September 2004 Sony unveiled the third major hardware revision (V12, model number SCPH-70000).
When it was released, the PS2 had many advanced features that were not present in other contemporary video game consoles, including its DVD capabilities and USB and IEEE 1394 expansion ports.