Yes if I remember correctly, near the door was my big FPS boost .
Don't understand why I had such high FPS, wasn't a bug either, seemed the same with Fraps also. I had the top spec hardware back then , WinXP minimum no processes, running GFX settings @ low @ graphics card control panel. The game was set to max though, I remember that gave me huge FPS boost.
Ummm I had that CPU on 64bit and 32bit OS with X800XTPE and 8800GTX and in stress test never got over that because it was simply crap. Wasn't a bottleneck it was more of trying to push a camel through the eye of a needle. Were you running LN2 or something because water and air never got me even half your claimed.