If you are using a mouse that has a built-in sensitivity switch, then it was his in the first place and should be used to adjust the speed of cursor movement. Usually this switch is a small-size extra button, pressing which activates the next level of customization. Sometimes this is done by using an additional wheel. For example, models of the firm A4Tech X7 this button is placed in front of the scroll wheel, and each press includes the following level of acceleration. This changes the backlight of the scroll wheel maximum acceleration corresponds to the orange-and-green flashing, and in the absence of acceleration, the backlight turns off and the wheel has its natural milky-white color.
If you want to disable acceleration, set in the settings of your operating system, in Windows this can be done through the control Panel. Open the main menu system by clicking the start button or pressing Win, and select the appropriate option. In the panel find the link to "Mouse" and clicking on it open the settings window. It consists of five tabs - click the one that is labeled "pointer Options". In the uppermost section ("Moving") placed the slider is set at half scale, you will turn off and the acceleration and deceleration of the pointer. Then click OK and change the settings will immediately take effect.
If disabling acceleration required in a certain game, you can ask it to trigger the corresponding program label. Click the game icon on the desktop, right-click and select in context menu the bottom line is "Properties". In the properties window find the "target" field and after the closing quotation mark with a space append the appropriate keys launch. For example, for the game ContrStrike dial -noforcemparms -noforcemacce.