A high speed receiver is provided using two parallel processing paths to enable rapid variable gain control. The parallel processing paths include a first processing path using a high resolution Discrete Fourier Transform (DFT), and a second processing path using a reduced DFT requiring fewer samples than the high resolution DFT. An initial sample of the data is processed using the second processing path with the reduced DFT by comparing a Fourier transform of the initial sample with predetermined threshold values. As a result of the comparison of the Fourier transform of the initial sample with the predetermined threshold values, a gain determination block determines whether a requirement exists for gain ranging. If gain ranging is needed, the gain of the data signal is adjusted and the gain ranging process repeats.