https://uvpackmaster.com/uvpackmaster-for-3ds-max/

UVPackmaster 2 is an efficient and fully-featured UV packing engine available also as a plugin for 3ds Max. Its robustness comes not only from the fact that it was written in C++ and runs as a multi-threaded application – it also provides a packing algorithm for Cuda-enabled GPUs (what gives a significant boost). In fact, it can perform some packing operations on all devices simultaneously: CPU and all GPUs in the system.