Battlefield 4 lags occur during loading screen or game play. This article highlights steps to fix the problem on different Windows platforms.
1. Disable Network Discovery
2. Disable ECN Packets
3. Optimize Background Services & Defrag Registry
4. Stop Universal Plug & Play Service
5. Disable Origin Notifications
6. Change Maximum Pre-Rendered Frames
7. Remove Saved Controls
8. Remove Corrupt License Files
9. Change Display Settings
10. Update your Drivers
11. Change Game Configurations
12. Change Undefined Monitor Number
13. Change Screen Resolution
I found these steps from this article. You can get more details from here:
Thankz]http://www.techtalkz.com/guides/529289-battlefield-4-lag-causes-tips-overcome-these-issues-pc.html#post2112044