The Antec Twelve Hundred conforms to the E-ATX form factor and so can accommodate motherboards with form factors ATX, Micro-ATX and Mini-ITX.
Its dimensions (LxWxH) are 513mm x 213mm x 581mm.
|Form Factor||E-ATX||Front Fans Size||120mm|
|Motherboard Form Factors||Top Fans||1|
|Material||Not sure||Top Fans Size||200mm|
|Color||Not sure||Side Fans||1|
|Expansion Slots||7||Side Fans Size||120mm|
|5.25″ Drive Bays||3||Rear Fans||2|
|3.5″ Drive Bays||9||Rear Fans Size||120mm|
|2.5" Drive Bays||0||IO Display Panel||yes|
|Tool-less Rails||no||Front USB 2.0 Slots||0|
|Length||513mm||Front USB 3.0 Slots||3|
The Antec Twelve Hundred has a the E-ATX form factor. Extended ATX is a slightly deeper version of the ATX standard which is designed to provide all the advantages of ATX but with slightly more room. Using the E-ATX standard, the case can house motherboards and power supplies with form factors ATX, Micro-ATX and Mini-ITX. The dimensions of the case itself (LxWxH) are 513mm x 213mm x 581mm.
The Antec Twelve Hundred has seven expansion slots, so there is plenty of room for extra components, which may be a deciding factor when planning on the longevity and build type of a PC system. The case has three 5.25" drive bays, which is enough to house an optical drive and a couple of hard drives, while still having space for plenty more HDDs with the nine 3.5" drive bays that are also available. There are no 2.5" drive bays, though, so any SSD or laptop-sized HDD installation would require an adapter.