Hey, thank you.Welcome to the forums, newcomer!
Make and model of your motherboard and your processor paired with said motherboard? You're advised not to use two mismatched ram sticks/kits to ensure stability. In fact using two different ram sticks are akin to you wearing two different sized clown shoes. They protect your feet, for sure but they only make you look silly. No, don't run X.M.P while on those two sticks of ram.