They're in theory fairly equal, however I suspect for gaming the i5 will edge out the AMD especially if you take overclocking into account. I'm still using an i5-760 (which is the 2.8GHz version of the i5-750) and have it overclocked to 3.5 GHz (all cores) and 4.0 GHz turbo (single core) and it doesn't bottleneck my R9 390. http://cpuboss.com/cpus/Intel-Core-i5-750-vs-AMD-Athlon-X4-760K
They're in theory fairly equal, however I suspect for gaming the i5 will edge out the AMD especially if you take overclocking into account. I'm still using an i5-760 (which is the 2.8GHz version of the i5-750) and have it overclocked to 3.5 GHz (all cores) and 4.0 GHz turbo (single core) and it doesn't bottleneck my R9 390. http://cpuboss.com/cpus/Intel-Core-i5-750-vs-AMD-Athlon-X4-760K