Hey, this is a little TuT or whatever you want to call it if you allways lagg ALOT on CoD.
Here are some solutions :
1, Download CCleaner, CCleaner is a defragmenting programme which will speed up your computer and delete all the files and stuff you don't need.
2, This is not the best solution : Put all of your graphics to the LOWER like the ScreenResolution, and other stuff.
3, You may need to update/buy a new graphics card, and it could be the same with your Monitor screen.
4, Not enough memory to run it?, well CCleaner will do this job aswell, sometimes when you keep everything you don't need on your computer and say you have like 10GB left or maybe less, you could lag because of that so you may need to delete alot of files of your computer.
5, Programmes you don't need running when you start your computer, as you may well know, when you start your computer 100's of programmes will start, and some of those programmes you don't need to be running, and it will just slow your computer down programme called GameBooster to help that aswell.
6, You can delete like so videos from your CoD files, because trailers and what not will slow your CoD down.
These are just solutions, and this could help your computer run faster aswell.
Me for creating all of it
BigPop for adding GameBooster.