apg slotOlder Expansion Slots on Motherboards 1. AGP Slot. Stands for Accelerated Graphics Port, this slot is available only in older motherboards to connect the graphics card for accelerating 3D output. AGP offers fasterFure 1 shows a Slot 1 Intel™ Motherboard with an AGP 1x2x4x video card slot; other features include, 5 PCI slots and one ISA slot. However it is not the purpose of this guide