I can't really classify it as a bug, but from patch 2.0 to EE, on all forums, people (including me) are annoyed by HUGE PERORMANCE LOSS.
I have a HD4890 1 GO, 4 go ram, core 2 quad 2.66GHz, windows xp sp3, I'm playing in 1280X1024 resolution with all ultra settings (except ubersampling), and I...