z77 slotZ77 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 CrossFireXThe Z77 Extreme4 expansion slot area features one PCI-e X16, one PCI-e X8, two PCI-e X1, and two PCI slots. A single graphics card will operate at X16 speeds, but two cards