All compact atx cases were too expensive for my liking, so I decided to make one. I should probably not suggest a case made of plastic, but if you have access to a 3D printer check this out. 288x207x343 mm in size and it can house full size ATX mobo and PSU and 3x 3.5" or 7x 2.5". Colling is silent and good, but I didnt test with more powerfull CPU or 3.5 HDDs