Loosing FPS on CS GO using NVENC

Hey guy as my title says i keep loosing 100fps ~ 150fps or more when i'm streaming and i'm using NVENC. This are my settings http://imgur.com/a/GjbJw i'm streaming to a secondary PC via LAN at 25.000 bitrate and then that PC encodes into 720p and sends to twitch. My PC is a i7 4790k at 4.2Ghz, GTX 970, 8Gb of RAM. Is there anything i'm doing wrong here? Thank you