Sample gameplay from an early part of Assassin's Creed 2 PC version. Provides some of the storyline, some wandering of the city via streets and rooftop, and some basic combat and assassination.
Game at 1920x1200, 4xAA, all other in-game settings at maximum.
Note that full details regarding the new DRM in Assassin's Creed 2 can be found here:
http://www.tweakguides.com/AC2_1.html
System specs:
http://www.tweakguides.com/Hardcon09_2.html#System
.