> The X11 underlying system changed some years ago. Before that, KDE3 and all
> other DE of that time had accurate settings for speed/acceleration. Now X11
> always applies some kind of acceleration depending on your input device.
Indeed, that's what the manual pages for xset and xinput say, though they elide the detials of 
what the acceleration formula is. xinput lists three parameters (accelNum, accelDenom, and 
threshold) but xset seems to only allow setting the first and the last one. In the end I couldn;t 
figure out how to get what I want.

And in case someone wonders why I want to have no acceleration and only speed: games. In 
particular, first-person shooters require making fast and precise movements, but that it is 
impossible with mouse acceleration. One either gets a precise movement (but then it has to be 
slow) or a fast movement (but then one loses control of precision).

Janek