The hardware design of an acquisition chain for gamma neutron discrimination is based on trade-offs between a large number of parameters. This paper describes the influence of the resolution, sampling frequency and Signal to Noise Ratio (SNR) of a digitizer on the performance of neutron gamma discrimination with EJ276 plastic scintillator. Thus, the study can help the user to select an adapted combination between these three parameters to obtain a good discrimination performance. The obtained results show that the SNR has the most important impact on the minimum sampling frequency required to perform the discrimination. The frequency can be reduced to 250 MHz if the SNR is higher than 4.