Maybe if you had an old nehalem or ivy or sandy bridge chip then yes you wouldn't be getting the highest frame rate possible. Even then thats not really bottle necking, granted the architecture of the cpu's is different bottle necking would i guess be having a 2 core g3258 and putting a titan in expecting to get a stable 60 fps it's just not going to happen. Even then bottle necking is subjective. But, no you're not bottle necking.