ATX is not a brand name. ATX refers to an international standard for computer components which makes it easy to swap parts.
The Power King ATX Power Supply features a 20+4-pin ATX power connector which means it was designed to work with atx motherboards.
I checked several resources. That power supply is a discontinued model. Detailed specifications are incomplete. I could not find any competent technical reviews. I also checked a huge manufacturer's database but came up blank. I cannot recommend that psu.