The SC743S1-650 black, 4U tower chassis supports a 12" x 13" Extended ATX motherboard and up to two Intel Pentium processors. For expansion, it features six PCI slots, eight 1" SCA Ultra320/160 hot-swap drive bays, two front USB ports, two 5.25" peripheral bays and one 5.25" floppy bay. It has a single channel SCSI backplane with SAF-TE. It comes with a 650W power supply.