We always recommend waiting for our review before taking the plunge on a brand-new CPU and its accoutrements, but gerbils who can't wait to trade in green portraits of presidents for AMD's many-core Threadripper CPUs can order a cooler with confidence thanks to AMD's official list of thermal solutions.
Most of the entries in the list are vendor-specific versions of Asetek's closed-loop liquid coolers, including units from Arctic Cooling, Cooler Master, Corsair, Cryorig, EVGA, NZXT, and Thermaltake. The Asetek-based coolers all use an adapter ring that comes inside Threadripper's large retail box. AMD's list also includes Arctic Cooling's Freezer 33 and Cooler Master's Hyper 212 TR Edition air coolers. We must note that Arctic's Freezer 33 product page specifically says the cooler is not intended for use with TR4 CPUs, so we figure that there may be an adapter bracket coming for that model.
Guru3D has a list of CPU coolers currently in production that will work with TR4 chips, but that require an adapter bracket that may not be included in the box, depending on their manufacturing date. This list includes water blocks from EKWB and AIO liquid coolers from Enermax.
We know of at least a couple of TR4-compatible coolers that are absent from AMD's list. Most notably, Noctua has three brand-new coolers designed for specifically for AMD's Threadripper and Epyc processors. According to Overclock3D.net, owners of older Noctua coolers should not expect the company to release adapter brackets to mate existing heatsinks to the AMD's biggest chips.
Cooler Master will be offering a mounting bracket (cleverly named RL-TR4B-MLLS-R1) that will let builders use its MasterLiquid Lite 120, MasterLiquid 120, and MasterLiquid 240 AIO coolers with TR4 processors. The company didn't say when this new part would be available or if it'd be free, though.
AMD says it will be actively updating its Thermal Solutions for AMD Ryzen Threadripper Processors page as new coolers are developed, so despite the additional info we found, the company's page is still the best source for cooler compatibility.