It isn't just the size of the power supply. It is also the standardized screw holes for the case. It is also the standardized cable connectors. In the past, Dell for instance had their own proprietary pin-out on the power supply cables.
I would recommend buying an ATX power supply, case and motherboard. Note there are different sizes within the ATX format.
ATX is a size. If you're getting an ATX mobo, you need to buy a case that will support the ATX mobo size. Most likely, the case will be sized for an ATX power supply, too. Read the specs for the case, and double check.
Agree. ATX power supplies are what you would use with most mobo/case. It's not really because your mobo is "ATX". Its because ATX power supplies are the standard for most cases. Unless you were making a mini pc with say a mini itx mobo and the case only fit an sfx powersupply.
It isn't just the size of the power supply. It is also the standardized screw holes for the case. It is also the standardized cable connectors. In the past, Dell for instance had their own proprietary pin-out on the power supply cables.
I would recommend buying an ATX power supply, case and motherboard. Note there are different sizes within the ATX format.