Unfortunately, this system is no longer in this config, so I can't take a shot of the rear. Anyhow, most slots are full... TNT2, empty, 10/100 NIC, usb2.0 card, PATA100 controller card, 56k modem, and ISA soundcard -- all on a BE6-II. The empty slot HAD a firewire card in it, but my homie needed it, so I gave it to him.