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 withThis guide covers UEFI tuning for ASUS Z77 motherboards, including P8Z77 series, Sabertooth Z77 and Republic of Gamers Maximus V series.