My configuration is as follows: Gigabyte GA-970A-UD3, AMD FX-6100, 4 GB DDR3-1600 DDR3 (single module Kingston HyperX KHX1600C9D3/4GX) and 2x Mushkin 992013 (997013) 2 GB DDR3-1600 DDR3 SDRAM. Problem is that BIOS won't let me set frequency on 1600 Mhz but only 1333. I have tryed all combination on slots. Help needed !!