How much DDR4 is needed for gaming?

[tommif]

I've currently got 8GBs of DDR3 and I was planning on upgrading to 16GBs by buying another stick. However my motherboard that I'm purchasing is for my Skylake CPU. This motherboard doesn't support DDR3 RAM. Should I go for 16GBs of DDR4 or 8GBs? How significant is the performance boost from DDR3 to DDR4?

 

[Tradesman1]

16GB in a 2x8GB config. As far as how high a freq you can run will depend on the CPU you choose. DDR4 starts at 2133