For ppl who already fallowed all intructions for have the in game working.. but STILL having problemas with fps drops.. i xplain u all why, well the WHY is unknow really.. how to solve it:
1 You most create a new shortcut from rage.exe inside whereever u have the game installed.
2 Modify the destination of the shortcut adding the "fix" (u all already should know but an example: C>Program Files>Id Software>RAGE>Rage.exe" +com_skipIntroVideo 1 +vt_maxPPF 8 +jobs_numthreads 0 +image_cacheMegs "1024" )
3 create a new note block, inside write somthing like this.. 1 example: "C:\Archivos de programa\Id Software\Rage\Rage - Acceso directo.lnk" (the " most be in it) Now as u may already can see on the example u most write the desitionation where the new shortcut is in, adding .lnk at the end.
4 Save it wherever name u want to save it.. but at the end write .bat

Done, thats it.. from now on you enter rage from that .bat file,if u want to create a new shortcut be sure to be from the .bat, and let it in the desktop. The fps drop problem should be fixed.. i know what everybody may think and say: "why da hell do all this sht for?" and the answer i really do not know it... it worked for me, before do this i had to recrete the shortcut and add the sht to it every time i wanted to play... with this .bat file solved my problem, and i decided it to share it with u all.

Also thinking in let the .bat here, but as manny may or may not know, manny virus are builded like .bat, and before you all think that, i preffered tell u all how to build it instead.

My comp:
E8400 3ghz core 2 duo
Ocz 2gb ddr2
Radeon HD 5670 1gb gddr5


Hope this solved your FPS drop problem as it did with me, and remember i write this with the only intention of helping.

(sorry for my bad english)