When playing black ops 2 i get 60 fps on any settings (even maxed out) but in sometimes i will get this weird lag, it says the games running at 60 fps but it feels laggy. I cant explain it but sometimes it will last a whole match and sometimes it wont lag at all.. Its very weird and it even does it if i turn the settings as low as they can go.. But it still tells me im at 60 fps when its happening.. My pc specs are - i7 2.4 ghz (3.5 max turbo boost), Nvidia 650m 2gb, 8gbs of ram..
Does it only happen with BO2? Does it happen only on certain maps or gametypes?
If so try re-installing the game, something may have been corrupted down the line.
Have you tried updating your video card drivers?
They release new drivers all the time, and recently added a new driver recently too.
Check to see if anything is running in the background such as:
Virus Scan or something updating.
Hope this helps.
Drivers up to date, nothing in the background, and it will happen on any gametype or map.. And it only happens on BO2.
Also make sure you don't have any other games downloading/uploading on Steam while you play. I had a similar issue a couple days ago where it felt like what you describe and it seemed to be caused by a game downloading a patch.