Building a PC shouldn't be complicated, that's why Antec created the One. 10 drive bays: 3 x 5.25"/ 5 x 3.5"/2 x 2.5". Motherboards: Standard ATX, microATX, Mini-ITX. Maximum graphics card length: 10.5" (266 mm). Maximum CPU cooler height: 6.1" (155 mm). Cooling system: 1 x 120 mm top exhaust fan - 1 x 120 mm rear exhaust fan - 1 x 120 mm side intake fan (optional) - 1 x 120 mm front intake fan (optional) - 1 x 120 mm / 140 mm bottom fan (optional). 7 expansion slots. Maximum-sized CPU cutout. Water cooling support: rear water cooling grommets (support -inch tubes). Bottom-mounted power supply with intake filter. No power supply included. Front I/O ports: 2 x USB 3.0 with included USB 2.0 adapter. Audio In/Out