r_lodbias 2 (a low value means more details, try something like 7)
Cvar limit is 2, nothing higher will do anything
other things for more fps or better gameplay:
cg_coronas 0
cg_atmosphericeffects 0
cg_bloodtime 0
cg_bloodflash 0
Check my topic for more cvars to help: http://forum.trackbase.net/threads/3...-Graphics-CFGs
And check if other processes are using your cpu or harddrive while you play, use process explorer, or any other software that shows you per-process cpu usage, and io history graphs.
p.s.
you say that cod4 takes more resources than et, I don't know how you checked this or you are just guessing it, but if it was true then you would have more fps in et than cod. If you have less in et it means et needs more resources than cod.
ET is CPU based, rather than using a graphics card. That's why I get high FPS on Skyrim but not on ET