Same problem here too. So Annoying!!
1950x (stock speeds) on an ASRock Taichi X399 (latest BIOS).
Getting idle of 48°C to 55°C and load up to 68°C (reading temps with HWMonitor and load testing with Prime95 and Cinebench). I can't get it to read anything above 68°C, but as this is AMDs max safe operating temp, I assume the chip is throttling at this point.
I've tried reseating the pump (with adding thermal paste), setting up fans in push, pull and push/pull with another 3 120mm. Pulling the front panel off the NZXT H700i doesn't help either.
I just contacted Enermax about it. Will let you know their response.