S-L-O-W! I get less than 15FPS worst-case framerate, sometimes even in empty corridors inside office complexes. STrangest thing is that setting resolution to 640x480x16 and low texture detail does nothing to improve framerate. Playing brings back memories when I had a TNT1 + K6/2-300 and I was playing Shogo (Lithtech 1.0 engine). It was a great game like NOLF, but ran slow as hell in seemingly simple levels. Of course, framerate of Shogo was better and I played it at 1024x768.
My current system is an Athlon Tbird 800mhz + GeForce SDR (140/200mhz). It's not a D3D configuration thing, 3dmarks give score of over 4900 (among highest for a GF SDR system) and I play dreaded Deus Ex at 1024x768/32bit without performance issues.