I have Gskill ddr3 1600 runs at 1333 i want to go 4 more gigs of ram at ddr3 1333 will they still run in Dual Channel if the 1600 runs at 1333?
Yep those are mobo default settings.
You have to set-up your ram to vendors specs in the bios.
Plus i would suggest you add the exact same ram kit as the old one.
Silly having a 1600Mhz kit and adding another kit that's 1333Mhz.