transcoding, cost and realization

Dear EvoStream Community & Support Team, i tried that transcoding thing, i transcoded 2 rtmp live streams into 360p and 240p streams so i have in total 6 streams. How ever my CPU is already 50% on all 4 cores and 8 threads. Current CPU -> Intel Xeon E5-1620v2 How i can provide 800-1000 incoming streams into 480p, 720p if just two streams need so much power. How are big live streaming sites doing it? Would it be a big effekt to use CPUs with 20cores and 40 threads? (Intel Xeon 2x E5-2670v2 20c/40t @2,5 GHz+/3,3 GHz+ and 256GB Ram) how many i rtmp live streams i could transcode then simultaneously? Also i need to provide these streams in HLS. One think i found is that we may use NVIDIA Graphiccards to Transcode. Do you have any ideas how we can achieve that together with evostream? Thank you for your time and help. best regards