Cod 4 lagg spikes/problems...

well it happends with every server. and my internet connection seems to be fine. ...

https://www.speedtest.net/result/2519776453.png

i also just realized, my CPU stays at 0% while playing games

OK, you said you updated all your drivers and I have to figure that you did from the Manufacturer and NOT from Windows Update... all I can say is to make sure you have updated/patched the game?

If you have done so, this is what I would do.

Download New Audio & Video Drivers from Manufacturer and Save to a Temp Folder
Download Patches if at all possible... sometimes patching from game does not take (I never do).
Uninstall the Game
Restart if asked, if not...
go immediately to: safe mode,
clean registry with CCleaner
Restart
Uninstall the Audio and Video drivers, do not restart until both are uninstalled.
If Nvidia card, do not forget to uninstall also PhsyX drivers/software from control panel
Restart computer, allow Win 7 to install Generic Drivers
Go to Safe Mode
Clean registry with CCcleaner
Restart
Go to Temp Folder where you save the Drivers,
Make Sub temp folders of each driver
Unrar or Uncompress within each folder
Right Click on .exe file and Run as Administrator
Do not Restart yet
Do the same with other Driver
Restart
Install Game, then install each subsequent patch, restart if asked.

Play Game as it should be... Good Luck

This is how I do my install/uninstall of drivers, people have different methods and different ways to do this... this is how it works for me