I recently got a new monitor (22" LDC), and fired up Episode One for the first time with it. To my great dismay, video playback while I was moving was horribly choppy. The choppiness was steady (not pausing but constant), and became highly apparent when my flashlight was on. I figured it had to do with lighting, and after messing in the video options for a little bit, I found that the source of the problem was HDR. The problem disappeared after I turned it off. What's odd is that the framerate dropped from a perfectly steady 60 FPS to a perfectly steady 30 FPS.
So my question is, what is bearing the weight of HDR? My graphics card or my RAM? I only have 1 GB of RAM, and an nVidia 7800 GT (256 MB). I wouldn't be surprised if it was either, but what concerns me is that I get perfect, unfaltering performance in Doom 3, and yet my computer can't seem to handle this.
Any ideas?