FPS issue between realms

Hi, I have an issue with the FPS:

- Lordaeron 20-30fps;
- Blackrock 20-30fps;
- Icecrown 60-70fps;

Same video settings, same spot @ Dalaran sewers, a lot of population around in all cases. I mean what could be the difference having such a smooth run on ICECROWN but not the others, I am doing PVP often and this affects my gameplay. I want to mention that I have patch with Legion models for feral druid, mounts and others but doesn't affect the FPS. Pls help!

NVM found the issue myself, apparently there was some addon, idk which but after disabling most of em I have 110 fps now.