z77 slotThe ram slots are 1 & 3 or 2 & 4 on dual channel boards. You can also watch the boot up from the power on, {turning off boot logo in the bios}. Or using4 slot ram ddr3 up to 32gb mulus lulus tes bukan servisan ada back panel. SILAHKAN PILIH MERK DAN SERI YG ADA DI VARIANT SEBELUM PAKING ADA TES ULANGNYA