yes it is that's why you should not.
first, in most recent games, cpu usage is going around %95-100 with 2500k while gpu usage is about %60-70, this is called bottleneck.
let me tell you what does bottleneck cause. there are two terms called %1 low %0.1 low that mean the lowest frame rate that system gives in those percentages. as i see on youtube, in most recent games those framerates goes around 25-40, cause stuttering.
second, as i see on youtube again, the cpu can't feed high-end cards and in titles like ac origins, frame rates don't even catch up 60 so my comment comes true. even at 5.0 ghz, i5 2500k can't give 60fps in new titles.