The H5 Flow does not appear to be a specific product mentioned in the search results, but NZXT's H5 Flow and H5 Flow RGB models are described as PC cases compatible with ATX, Micro-ATX, Mini-ITX and E-ATX motherboards. These cases support ATX power supplies, with a maximum length of 200 mm.

If the product 'H5 Flow' refers to one of the H5 Flow or H5 Flow RGB models, then yes, it supports ATX power supplies. However, the manufacturer code "CC-H51FW-01" does not match the codes mentioned for the H5 Flow or H5 Flow RGB models, which are "CC-H52FW-01" and "CC-H52FB-01" respectively. This could be a different model or an error in the manufacturer's code.