ATX cases hold mATX MBs???

As the title says, can ATX cases hold micro ATX boards? With my limited experience (1 chieftec full tower case), I'd say yes they can hold both mATX and ATX. On my case there are holes positioned in numerous places, allowing different boards to be mounted. But I didnt know if this was how all/most cases were.

Also, do mid/full towers hold a certain size PSU? Or are there different size PSUs?

this is how most higher quality cases are. some cheapo cases only come with some mounting bracket positions, and unless you want to drill/cut a new one in the mobo tray, then it might not work.

If my 8" x 10" Soyo SY-7IWM/L mobo qualifies as mATX, then an ATX case should fit fine. But if some of the holes in the corners of the mobo don't line up, put a standoff under them anyway or the mobo may flex enough to short to the case.

Thanks, I'm thinking I'll prolly go with a "better" case anyways, like Chieftec. Antec, or the like. As they are not too expensive. But I wan't sure how the cheaper cases were made.

Anyone know if PSUs are made different sizes, or otherwise might have tough times fitting in some cases? I think they are made for mATX and ATX cases, but I wasn't sure.