This from the embassy website.
" Visa processing times (including day of submission and day of pickup)* 3 working days for Tourist visas, Non-Immigrant Labour visas for Cambodian migrant workers (for example, if you apply on Monday, you can pick up your passport on Wendesday) 5 working days for other Non-Immigrant visas (for example, if you apply on Monday, you can pick up your passport on the next Monday)"
Source: https://phnompenh.thaiembassy.org/en/publicservice/steps-to-take-for-traveling-to-thailand-as-a-foreigner?page=5d73b14415e39c46f40076a1&menu=5f4a095203523246a464a632