The ASUS P8H67-M EVO comes with two PCI Express x16 slots, one PCI Express x1 slot, and one standard PCI slot. The first PCI Express x16 slot (blue) always works at x16 speed, while the second one (black), always works at x4 speed, supporting CrossFireX. The presence of two PCI Express x16 slots is a very unique feature for a microATX motherboard, because motherboards based on this form factor usually have only one. This allows you to build a high-end gaming system with two video cards in a very small case. The first PCI Express x16 slot supports a dual-slot video card, but if you want to install a dual-slot video card in the second slot, you will have to make sure that your case has at least five expansion slots. (Some small cases have only four.) Also, you will block the USB headers located on the motherboard edge.
The Intel H67 chipset doesn’t support standard PCI slots anymore, so the support for these slots is provided by an ASMedia ASM1083 bridge chip.