Q: How do I set the mouse speed under X windows?
A: If you want to set your mouse speed in X, you have to use the xset command. Your mouse speed is controlled by acceleration and threshold levels. The command synopsis is
xset m acceleration threshold.
xset m 4 1
Acceleration defines how many times faster the cursor will move than the default speed, when the cursor moves more than threshold pixels in a short time. Acceleration can be a fraction, so if you want to slow down the mouse you can use 1/2, and if 3 is slightly too fast, but 2 is too slow, you can use 5/2. You effectively disable the threshold by setting it to 1, that way the cursor will always move the same speed. To get the default settings back, type
xset m default. You can add the xset command to your ~/.xinitrc to get the desired mouse speed every time X starts.
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