New monitor, new dpi please help me :d

[GhozT]

Hi everyone im have a question:

Previusly im play in a 18 in ~ monitor and i havest a 1440 x 900 resolutión thats resolution is 16:10, and i have 1600 dpi on my mouse.

Every looks fine but thats the problem.

I bought a new monitor it is 21.5 in and 1920 x 1080 thats it a 16:9 aspect ratio and i have the same dpi and, but i feel the mouse more slower, im read a lot of forums about the dpi dont changes when you play in another monitor but im think this is fake, im test it with a lot of resolutions...

Now im playing with 1650 x 1080 resolution thats it 16:10 aspect ratio, i have "almost same feel", but i have black borders...

Question:What is the dpi i need to put to feel the same, but in 1920x1080 (the same of my first monitor), i hope can help me Thanks.