What's the practical difference between raising sensitivity and raising DPI?

Question

I recently purchased a mouse. My old one was fixed at 1,000 DPI, so the only way that I could make a mouse more sensitive (i.e., I need to physically move my hand less to move the cursor the same distance) was to raise the sensitivity, either in-game or in the Windows mouse settings. However, my new mouse supports a variable DPI, ranging from 500 to 6400, so now I have another way of making my mouse more sensitive. But what's the difference between raising my DPI and raising my mouse sensitivity?

For example, if I am playing a shooter game using an in-game sensitivity of 1 and a DPI of 1,000 and then I switch to an in-game sensitivity of 2 and a DPI of 500, the perceived sensitivity will be the same. However, could the change in sensitivity and DPI result in any subtle changes? Like the mouse informing the computer about its position more often, or anything of the sorts?

Answer 1

DPI is dots per inch, so the number of points, that you mouse read is you move it one inch forward. It's some kind in accuracy. The sensitivity is the reaction on some number of dots. So if you have the double of sensitivity, you need only the half of dots and you don't have to move your hand with such a big amplitude as before. There is also another factor of acceleration of your movement. With the higher dpi the acceleration can be recognized much better.

Answer 2

The basic idea is that higher DPI is more precise. But practically, these days DPI is mainly used as marketing argument for selling expensive mice.

Generally, it's best to find a setting that suits you well and use it, and don't worry about it any further. It is unlikely that a mouse you bought today is not precise enough because of low DPI.

Personally, I also find that I often accidentally touch the change DPI switch on my mouse, so I disabled the functionality to change DPI on the fly in the driver UI.