Reddit user that goes under the "callingthewolf" call-sign has managed to push the Threadripper 1950X from 3.4GHz base clock to 4.0GHz at 1.25V Vcore and to 4.1GHz with slightly higher 1.4V Vcore. What makes this overclocking feat interesting is the fact that it was done by using Thermaltake's Water 3.0 liquid cooler, suggesting that we might see even higher overclocking records as soon as extreme overclockers get it under LN2.
The overclocking was done on an ASRock motherboard and eight 8GB 3066MHz DDR4 memory modules. At 4.1GHz, the overclocked Threadripper 1950X managed to score 4548 single-core and 58391 multi-core score in Geekbench 3 and 3337 point score in Cinebench R15 at 4.0GHz.
While these scores are not a record breaking results, these do show that Threadripper scales nicely when overclocked and that there is certainly a lot of overclocking potential left and shows that AMD made a good move by using the indium solder with gold plated dies to attach the IHS (Integrated Heat Spreader).
You can check out the full Reddit post for more information.