A gpu can never 'bottleneck' the cpu, only the other way around, and in that sense, the term 'bottleneck' only refers to the fact that basically the data comes from the HD, through the cpu, to the gpu, to the monitor. If you have a slower cpu, or not enough cores to handle the amount of data in a timely manner, then the amount of data passed to the gpu is less than the gpu can pass to the monitor, or in layman's terms, you get less frames.
For an i3, the gtx760 is a balanced match, the cpu can only work so fast, and the amount of data passed to the 760 is fine. Pairing a 770, r9 290 etc, is just overkill on the gpu side, since the cpu will not send enough data to adequately utilize the gpu' capabilities.