Nvidia Quadro m6000 (12gb) question for T3600

Do Quadro M6000s typically bottleneck in Dell Precision's T3600s?

I ask because for the little bit that I was running an m6000 in my T3600, I was having issues with dropping frame rates, stuttering, and laggy shooting while playing GTA 5 Online (for example it would take 3 headshots to take down other player characters; while on a gtx 1080 ti I had none of these issues).

Mind you I didnt really notice these differences until I switched from an m6000 to a gtx 1080 ti and then back to a m6000.