I was perusing the Steam Forums and came across a bump-happy poster (my internet is acting up so I can't pull up the link again) who suggested that NVidia's 67.02 beta driver fixed his NVidia problems, AND enabled DX9 functionality. A pretty tall claim, but I'll check it out myself and update everyone. My 5900 is going to have to suffice until I fix my 9800 Pro... Download Edit: After forcing DX9, I realized why Valve chose not to enable DX9 on NVidia cards. My framerates dropped from the 40s to about 8fps, AND none of the shaders worked right. So much for that fix, eh. Now I'll test for stuttering at DX8.1 and tell you how it goes. EDIT 2: Level save stuttering is fixed! Framerates are up! Water can be set to "Reflect All" pretty much without a frame hit. Excellent. Still not DX9, though.