No, the use of DDR3 will NOT limit gaming performance anytime in the near future. DDR4 has not even been released yet and will initially become available with the X99 chipset (a.k.a. Haswell-E) by end of 2 Qtr this year. Rumors are being passed on tech websites that Haswell-E might be released a bit late (3rd Qtr) due to non-availability of DDR4 modules. A new X99 motherboard isn't going to be usable without the correct memory to use with it. Bottom line, don't sweat it. DDR3 has at least another two years of life left before being phased out.