Hade en sida som bokmärken om detta, minns att jag hade lite problem själv med det, copy and paste till dig här i tråden så får du prova dig fram.
"Check the setting of com_maxfps for starters. Make sure it isn't a low number, it should be at least the 40s or up. Next, try setting cg_drawfps to 1. Look near your kill-counter to see your FPS. If your FPS number is low when you lag, you have CPU based lag. If you have a high FPS number but still lag, it is connection lag. A high ping also determines connection lag, such as 400+, which you can check while pressing tab. Check the cfg section of this forum and try my low graphics cfg to reduce cpu lag."
-----ISDN Single (64K)---------
cl_maxpackets "30"
cl_packetdup "1"
snaps "20"
rate "7000"
---ISDN MultiConection/DSL (128K)---
cl_maxpackets "60"
cl_packetdup "1"
snaps "20"
rate "15000"
----DSL 256K or faster-----
cl_maxpackets "100"
cl_packetdup "1"
snaps "20"
rate "25000"