Which specific model epcys? And if it's not too much to ask which motherboard and power supply? I'm really interested in building something similar

Looking at https://news.ycombinator.com/submitted?id=DrPhish it's probably this machine https://rentry.co/miqumaxx

  * Gigabyte MZ73-LM1 with two AMD EPYC GENOA 9334 QS 64c/128t
  * 24 sticks of M321R4GA3BB6-CQK 32GB DDR5-4800 RDIMM PC5-38400R
  * 24GB A5000