Dell Inspiron 15 3501

Hi there,
Is there any significant differences performance wise between a dual channel 4GB & 4GB configuration and a flex mode 4GB & 8GB configuration? (On an Intel mainboard) (RAMs are DDR4 with 3200MHz clock rates) Does it really make a difference to choose the 4,8 flex mode configuration over the 4,4 dual channel? Can i upgrade my ram 4 to 8+8 will it be a problem. want to work with multiple applications opened without every application freezing displaying the "Not responding" .I'm basically looking for faster performance, shorter latency and the ability to work with multiple applications simultaneously.