Here a little list of mostly older but also demanding games not only at their releases:
Half Life 1
Unreal 1+2
Aquanox
Dungeon Keeper 2
Morrowind
Max Payne 2
Far Cry
F.E.A.R.
The Elder Scrolls IV: Oblivion
Splinter Cell: Double Agent
Crysis 1+3
Metro 2033
Battlefield 3