I've heard that hl2 should work on lower end systems, but i've got an ok system and i keep chugging bad. FPS keeps dropping and raising back and forth from like 10 to 60, but all i want it do is have it remain constant. But its so annoying and getting harder and harder to play because of this chugging. My system is:

Radeon 9600 XT 256mb Drivers up to date
1.7 GHZ P4
256 PC-133 SDRAM

I'm running 640 x 480 resolution, model detail med., tex. med, no shadows/ shaders on, no filtering or AA, water detail low, etc. And I still cant get a constant framerate.

Does anyone have any suggestions to get a better framerate without having to tone down the settings? (Yes, i really don't want to play hl2 on lowest settings SAVE ME)

*I've already tried the guide at gamefaqs.com