I made a guide for PA once now I'll just repost it with modifications so people can understand lol.
Type this in console to show your frame rate, the higher the better: /cg_drawfps 1
set r_picmip <n>
The bigger the number is, the crappier your game looks, but it may improve performance on older video cards. Default number for n is 1. Allowed number are from 0 to 3.
For example, type in console: /set r_picmip 2
set cg_wolfparticles <n>
You notice that the game lags whenever there is an air or artillery strike, so type in console: /set cg_wolfparticles 0
You can see through airstrikes more easier. Downside is you might run into one.
If you don't like it type: /set cg_wolfparticles 1
Then your game will be normal again.
set cg_atmosphericeffects <n>
Turns on/off effects like rain or snow. There's really no reason why you would ever want this to be on, it just makes it harder to see and makes everything laggier.
Type in console to turn off weather effects: /set cg_atmosphericeffects 0
set r_detailtextures <n>
When detail textures are enabled (n=1), it means that basically every object is textured twice to make it look more detailed. Obviously this is slower, so try disabling this (n=0) if you want to get more frames into your system.
Type in console: /set r_detailtextures 0
set r_fastsky <n>
If you don't care about the color of the sky, then type this in console:
/set r_fastsky 1
If you want your old sky back, type: /set r_fastsky 0
Internet and Networking tweaks:
This helps me reduce my lag.
/set rate 25000
/set snaps 30
/set cl_maxpackets 50
Or simply use Logical's console cfg.
Pretty much still a work in progress.