z77 slot32GB. Expansion Slots. PCI Slots, 1 xPCI Express 3.0 *2.0 x16 slot (x16 mode) 1 xPCI Express 2.0 x16 slot (maximum x4 mode, compatible withZ77 Pro3 · 100% All Solid Capacitor Desn · Di Power Desn · Supports Dual Channel DDR3 2800+(OC) · 1 PCIe 3.0 x16, Supports AMD Quad CrossFireX™ and CrossFireX