Embodiments of the disclosure provide a gate driver, a display apparatus and a method for controlling the gate driver. The gate driver comprises a plurality of clock signal terminals; a controlling signal terminal; and N stages of cascaded gate driving circuits. Each of the N stages of cascaded gate driving circuits is configured to pull-up a voltage of an outputting terminal of the gate driving circuit according to a signal at the respective clock signal terminal, and to perform a noise reduction operation according to a signal at the controlling signal terminal. A controller is coupled with the clock signal terminals and the controlling signal terminal, and is configured to detect signals at the plurality of clock signal terminals, and to output a valid level signal to the controlling signal terminal in response to the signal at the clock signal terminal being abnormal.