Native dpi on any good mouse these days is in steps of 50, hence almost every dpi that you're gonna use is native, except stupidly high ones >6400.

edit - re-read your comment and I think you mean the physically true dpi, which still doesn't really matter as its like zooming in on an image. There's a point where u can't tell what the original image is but it takes a while to get there.

ok so the benefits of a high dpi is that there is more inputs from the mouse per movement of your hand into the game, in a sense this makes it more "accurate" because you can make finer movements. A benefit of this is if your mouse fucks up one input of movement it has less effect on the outcome of your aim as it is smoothed out by the increased amount of other inputs per movement.

A benefit for lower dpi is that small accidental movements, such as a movement of below 0.062 mm for 400 dpi wont be read. Technically this makes your aim more precise as your slight changes in repetitive movements is reduced.

Overall most of its bullshit, mostly recommend a sens below 2.72 due to pixel skipping, raw input on, and any dpi that u like unless you have an old mouse in which case look up native dpi, unless its ridiculous high cause source is a bitch with super high dpi's.

Negative acceleration my dude, your dpi is so high that you reach the edge of your screen in windows before the mouse can be re centered so the rest of your movements are not counted till the next frame where windows re-centers the mouse again. Just turn raw input to 1 and you should be fine, then tf2 will read movements straight from your mouse and not through windows.

also pls turn your sens down to dpi 3200, ingame 1.38, its the same but better

This http://arcanesanctum.net/negativescreen/ and using http://arcanesanctum.net/colormatrix-viewer/ to find the correct colour matrix should help you out my friend